Hi.
Some things could really make this MMO attractive. What I have noticed so far and from talking to people, is that the community tends to have the same purpose for playing; the Spiral Knights community tends to come on to play for a relaxing, fun thing to do with free/extra time to waste. Many people are just looking for a social and friendly environment to come to. And that is great.
The developers have, regardless, done a great job trying to reach out to the playerbase that wants to have a ridiculous challenge by adding Danger Missions. Danger Missions, although some easier than others, provide this and were a very smart addition; I love them. The devs have been occupied making danger missions, which are a great way for them to spend their time.
This game can, however, reach out to different playerbases and become much more popular. Below are my suggestions.
1. Lore
The NPCs aren't very interesting, except for maybe one or two that stands out, and there isn't much lore to this game. Artifacts would be a great way to give players background information about silly things that explain the world of Cradle to them. Things like heavy lore are what engages players and truly gets them into the game. The Role-playing playerbase in rather large MMOs, such as World of Warcraft, is massive. This playerbase is a huge source of money for Blizzard, and could be just as beneficial to this game as well.
Improvements: Make NPCs interact with players more, rather than just talk to them with some information or service. Make them do something that makes the unique and memorable. Add more lore through many new Artifacts that can randomly drop from monsters or be found in treasure boxes etc, which gives background information about certain monsters / levels / things that make the world of Cradle more interesting and more revealed to us (I feel many things about Cradle are kept secret from us, such as information about the Owlite Scholars for example). To take this a bit further, make Artifacts something to be collected by players. These need not be rare, although some can be.
1.2: Get it over with, get something new. Referring to the storyline of this game. "We need to reach the core to power our ship" will not keep people on the edge of their seats forever. Eventually, we will fall off of our chairs with boredom due to zero result. Sticking to the same storyline and purpose for helping the Spiral Order will make players bored.
Common Misconception: "Ending the storyline and giving the knights a result of wether or not we power the Skylark and defeat the swarm / Crimson Order will end this game and make it no longer playable." I reply to this: absolutely no it does not end the game. Patches that change Cradle and the Spiral Order forever. New things, new threats. Those are what truly keep a player interested in a game for a long time.
This suggestion below would reach out to the old, loyal playerbase. This will get old players back into the game.
Improvements: We need to end this current storyline, have something happen to draw the conclusion of what we have been doing since this game was released:
Either "NO. Spiral Knights will never get to leave Cradle. We got rid of the Swarm / Crimson Order, and we now have a new threat: The blah blah blah! While we deal with the blah blah blah, we must learn to live on and accept our new home"
Or "YES. The Spiral Knights will return to their home with the Skylark, although many prefer to stay behind and live on Cradle and to protect it (us, the Spiral Knight players). In fact, there is a new thing threatening Cradle which will be our first true test to prove ourselves as the protectors of Cradle: The blah blah blah!"
Then, this "new threat" is what occupies us. This will be brought into the game as a free "expansion" to all players (since this is a F2P game); one omega patch that may change Cradle forever, although keep the old missions of course.
2. Greater rewards
There is a strong playerbase that wants to have a reward or wants something shiny to work towards. In Spiral Knights, the only rare drop item we have is the Darkfang Shield. All items are guaranteed to be ours once we craft them, and the current "rewards" people are working towards are amazing UVs. While rolling great UVs will entertain some players for a long time, many players want something more.
Improvements: Add more of a reward for playing Spiral Knights. Currently, there are no rewards for Danger Mission completion. Something like costumes or accessories that show players have completed every single Danger Mission in T3 or achievements associated with Danger Missions will give them something more to do and something to look forward to. Second, there are no rewards for Lockdown Leaderboard rankings. Adding costume or accessory rewards to the top players on the Leaderboards will give players something to "show off" and make them feel like they have accomplished something. Currently, prestige only rewards a symbol near a name. Costume and accessory rewards are also appropriate for prestigious players.
Achievements can use more additions. Difficult achievements, such as completing the Royal Jelly Palace without receiving damage, can give players a fun challenge and a great reward to work towards. An achievement that rewards a special Mining hat with a mineral, say Luminite, on top of it can be given to players that do something ridiculous with Minerals, such as deposit 10,000 within one 10 minute period. These are just examples off of the top of my head that can expand the achievement systems.
3. Environment
The environment in Haven is bright and happy. It is supposed to have that "safe" feeling. This is good and relaxing for most, although some people agree with me that staying in Haven all the time can make an environment boring. Some people like to hang out in Moorcroft Manor or Emberlight. In these places it isn't quite the same as Haven. It is darker and more dangerous, and the music fits this.
One playerbase loves to be in Haven. A different playerbase finds this bright and happy town unattractive.
Improvements: Make a second "Haven" by adding anything that was accessible above ground (Accessory attaching, auction houses, vendors) to be accessible below ground in a new town. This new town could perhaps be a town revealing the true number of Gremlin outcasts of the Crimson Order, featuring mostly interactable Gremlins rather than Spiral Knight NPCs. Players can have the option to "set their home" in Haven or the new town. By "setting their home", they will always be thrown from that town to their missions, and then back to that town. There will be an elevator of sorts that allows access between Haven and this new town.
Seasonal Changes: Much like in winter when Haven receives snow, add other types of seasonal or time-of-day changes that make Haven feel less robotic and more alive.
4. More personal choices and "factions"
Many people like having the option to make choices which define their character. To either Spit on someone needing help or to kindly assist them, people love to have the choice surprisingly. Of course... these choices aren't going to necessarily be the one example I have provided. Something that goes along with personal choices are "factions" of NPCs. Choosing to assist one group of people, or choosing to assist another group gives players another chance to define their character more.
Improvements: In Spiral Knights, there are two distinct friendly "factions" of us. 1. "The Spiral Order." We are currently helping the Spiral Order and have no choice otherwise. 2. "The Gremlin Outcasts" from the Crimson Order. (Note: The Gremlin Outcasts are like Punch. they are friendly to us knights and the Spiral Order; they are against the Crimson Order) You do not need to make the cliche "reputation levels" and such unless it seems most fitting. Mission text and objectives can be altered based on Knights' preferences: helping The Spiral Order or helping The Gremlin Outcasts. Players can also help both. The Spiral Order already exists, we are currently helping them reach the core etc. The Gremlin Outcasts would need to be expanded for this idea and there needs to be missions associated with them.
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Summary: (Note: This is NOT A TL;DR! My reasons are all ABOVE)
Just so people do not take in my suggestion the wrong way, you cannot take me 100% literally. A lot of what I said are just examples. You might reply that a reward for Lockdown Leaderboards is a terrible idea. I can partially agree, that was just an example I had at the top of my head; not my actual suggestion and reason of posting.
These are my actual suggestions in a nutshell:
1. Add more lore, and make the NPCs more intersting and memorable.
1.2: Get done with this current storyline of saving Cradle already. Make a new one to keep us occupied, while keeping the old missions for new players and memories.
2. Give us greater rewards for completing difficult feats, and add more items that are rare. Give us more things to work towards.
3. Add different environments.
4. Add "Factions" or different groups of people that we help besides the Spiral Order. Also, let there be more personal choices. Simply adding 3 or 4 options of how to reply to an NPC for different reactions would do.
These would expand this MMO by reaching out to more diverse playerbases.
First off, I don't really agree with you on the danger missions thing, they're still not really a significant challenge. However, all I need is some form of a challenge and I'm good, so I like them.
Staying behind for [scraps] and giggles isn't anywhere near as compelling as trying to get home. The core stays closed, forever - but any number of new story lines (particularly those revolving around the crimson order) could be introduced. The central plot can be advanced and fleshed out - we could preform an investigation of the skylark wreckage, we could chase down the artifact stolen by that creepy gremlin in the new user experience - any number of things could happen that offer hope for salvation that is ultimately dashed, or you discover that you have just found one piece to the puzzle - and more pieces present themselves indefinitely.
Rewards - One time rewards for bosses, danger missions, etc. are nice, but the LD leaderboards and prestige are meaningless stats that should have no real rewards unless they are changed to be meaningful.
Enviroments - Expand emberlight and moorcraft, make all crown fees go away, make them able to contain multiple players like haven is. No need to create totally new areas.
Factions - You haven't really fleshed out your ideas here, but I don't really want a bunch of different affiliations in a co-op game. That said, different plot-related NPC groups of knights that you can interact with and hence gain access to new content etc. could make a good plot point.