It's possible that in the future, as disk space and bandwidth gets cheaper and server processing power gets faster, we will be able to increase the number of icons a free account can use; I can't guarantee it, but it's possible.

I am happy to hear this. Fifteen feels somewhat constraining, but sometimes if one anticipates needing only 20-30 icons it can make the decision on whether to stick with the free or go for the paid rather difficult, if only because it'd feel like all the unused icon slots are going to waste. I guess what I mean to say is that the gap between 15 and 100 is rather . . . gaping.