Stick to the cobalt set.
By doing missions, you unlock the recipes for the cobalt set, thus saving you a ton of money (as there is a sword, shield, helmet, armor, etc.

^ The wolver sets are pretty much OP, considering they can each get elemental, piercing and shadow defense for each set respectively. They also have boosts for swords too. However, that is only if you are a swordsman

Gunners and Bombers got their own sets too.

*(((This is a COMPLETE guide for newcomers skip to paragraph 3 if you want to read middle game.)))*

Takes quite a large amount of time to actually make crowns. My first 100k took me about... 2 months? You can achieve that amount of crowns much faster honestly but I was new to the game back then. I've been playing for 2 years now and I pretty much know about every aspect there is to making crowns anyway here is a guide that gives a good bit of info on how to make them. Enjoy! :)

First when you start off in SK there won't be much info to take in because you don't have friends yet. But try to make some and ask them about game mechanics to get more knowledge on the game. Then you should be familiar with some of the game mechanics and you'll be able you embark on your journey into the Clockworks. Now after a few depths that you've done for training do missions with your friends or just anyone in general make sure you do enough of them to get to the Lair of Snarbolax mission where you get most of your early crowns. Do that a few times until you receive a total ten tokens from it. Once you've done that find Brinks or Sullivan they're the Npc's who take in the tokens and give you items in return. Get a sword with your tokens and use it on Snarbolax runs until you get armor that defends you from piercing damage. Armor and weaponry can be obtained from the Auction house, Npc's, or it can be crafted.

Now since you have at least 2 star equipment go and do missions all the way to Royal Jelly King. You should have 10k crowns if you've been saving. Use it on Wolver armor or shadow weapons since they're best for the situation right now. After that you can do the Jelly King mission and not be such a push over to the Slimes compared to before. Now do the Jelly King mission until you get to 0-9 mist energy and after that wait another day to do it again make sure you use all of the mist energy you can in one day. Only do the first 2 depths of the mission though as you are not ready to fight the boss just yet also please don't try to be a hero and revive yourself or else you will be short on energy AND crowns. Once you've done this for a week straight or so you should have 60k-70k crowns. Amazing right? Now go spend it on recipes or just buy the 3 star item(s) directly (Don't buy 4 star or 5 star directly although only do it up to 3 star.) to help you get full 3 star don't buy a Sealed Sword because once you can fight JK you'd just be wasting your crowns on it same goes for Antigua.

Now do 2-5 weeks of JK runs per day and you will have enough crowns to purchase recipes for 4 star items. Do more missions and get to the Roarmulous Twins mission and get enough tokens to get a pulsar and then upgrade it. This will help you much more on the defensive side, considering it pushes enemies away from you. If you have friends who regularly do FSC runs at this point. Ask to join them! Make sure you also do a few JK runs if you can't afford to upgrade your pulsar yet. But yeah if you join them then you will be able to rack up tons of crowns per week even more than JK runs! So make sure you do that all the way until you can get 5 star armor.

Anyway that's how I arrived at where I am now. Hopefully you can get there too! Hope this helped out a bit. Good luck! :D

Don't spend your CE on running missions or running the clockworks until you are outfitted for JK. Don't spend energy on revives at all, bring teammates who can and will pick you up. Learn to use the auction house and sell your extra materials. Learn to play the coliseum games if you need something to do when out of mist. Once you can run JK or other profitable missions (or profitable arcade gates) you can spend CE running.

If you just break even on crowns earned vs. cost to replace energy, then you've profited by the heat and materials, so that's a measure I use on whether or not areas are worth doing at all on CE. If you just run out your mist every day you should easily be saving up 30k crowns per week.

If you can only play 2 hours a week, you might as well give up now. I have to play two hours a DAY just to make sure my mist energy doesn't go to waste.