Perhaps there could be upgrades for the mist tank, such as the amount it holds or charge time reduction upgrades. For those who don't play everyday, or go out of town for a couple of days etc. this would be really great. I was out of town for the weekend with no chance of playing Spiral Knights, and I came to think that perhaps if there were mist tank upgrades, I could have stored up more than 100, but 300 for the three days I was gone. A charge time reduction would benifit the impatient, however I myself find that it would be somewhat useful in regards to wanting to play multipul times per day without having to buy crystal energy to sustain me. A few times I have seen knights standing around waiting for their mist tank to charge back up, and perhaps with a purchasable upgrade, they could stand around waiting for their mist tank to recharge.

This is my idea of the day, what do you guys think?