First off, I largely agree that it would be great if Spiral Knights received advertising. However, as outlined by the development team, this is impractical. Advertising is expensive. period. But that's neither here nor there.
What I really want to pose to our community is that advertising CAN be accomplished: by the players. What made some of the most popular games (as of 2018) so successful? Think of *ahem* Fortnite... Twitch. Youtube. Twitter. A Constant Social-Media Presence. These forms of media and their respective content creators reach out to larger audiences and grow game communities.
For this reason, I want to first thank some great SK content creators; Rynth and Chawkthree are two particular creators that I enjoy. Feel free to recommend some more in the reply section :)
What I'm trying to say is... While we all dream of logging in to Steam and seeing a Spiral Knights ad, if we really hope to attract new eyes to this awesome game, we have to do some of the work ourselves. So, let's do it! Go make cool Youtube videos, showing off the game; Go and stream!
This was something that, as a returning player, I REALLY wanted to talk about. I think everyone that visits these forums really value and cherish this game. With that being said, I hope that more players create videos, stream clockwork runs, etc.
Anyways, I hope this was decent for my first real Forum post lol.
Interaction with an audience is a huge marketing strategy now-a-days, and it's completely free to the company doing it. Spiral Knights likely never pulled many people in from actually paid advertisements, thus the word of mouth carried it forwards.
I mentioned this in a recent thread, but Three Rings/Grey Havens likely have access to data regarding the return on investment for various forms of advertising. I highly doubt that, with a smaller budget (this is an assumption at least), they would be trying to ramp up advertising in a way that isn't proven to work for them. I want to say cross promotions are their best bet, and I absolutely believe that a cross promotion between Slime Rancher and Spiral Knights would be not just fitting (seeing as both Grey Havens and Monomi Park come from the same Three Rings family) but a perfect thematic promotion.
That being said, we have some wonderful content creators even today! We have amazing artists, excellent music creators, video creators (both serious and silly), and as of recently, some great community-oriented livestreams!
I try to dig my hands into community strongholds myself - while my presence on the forums has declined a bit, I'm helping run the Spiral Knights Discord Server on my free time, and help manage the subreddit as well. I also totally-don't-provoke(with-food) the game masters on Twitter, which they aren't always the most active on, but still maintain a presence at.
Personally, I believe that Grey Havens doesn't need any more advertising - the players do that for them. However, the important part is to maintain the playerbase. I believe what Grey Havens really needs is a dedicated and official Community Manager - someone whose primary concern is to rally the community together, talk to the community to get their thoughts, and relay that information back to the rest of the staff to build up game plans. Once they have someone who not just negates the silence between the team and the playerbase, but actively talks back and forth with them, that's when we'll get some of those "glory days" back that old players are so fond of... Even if the actual development is a bit slow.