There seems to be waaay too many complaints and whatnots in the forums, so I make this thread especially for the unsung praises for Spiral Knights!
I'll start from the most obvious topic to tackle: Energy.
I'm still pretty new and I can see why people would hate it, but I honestly like the Energy system! It's a good (though artificial) limit on my playtime, keeping the game from getting boring too quickly. It's also a great incentive to come back and play everyday, since after 22 hours Mist Energy will practically be wasted. Crystal Energies is a good business model for OOO, and they're not very expensive in both real money and Crowns. So all in all, I think it's great!
One thing I like about the game that I don't hear much about is the music. I'm extremely picky when it comes to music, but I love the music in Spiral Knights!
That's all I have to praise for now. Remember, no complaining in this thread!
(..When I think about it, I'm complaining about people complaining. Here's a funny video to make up for that http://www.youtube.com/watch?v=gfzLyPqko8w )
Good luck with that no complaining bit.