There really should be more things to spend your money on. I have 600.000 at this moment can't do anything with it, so its just there waiting to be stolen...
when you level up your hero you can see how much DPS he increases the next level, it would be nice if you also could see that when you push the button for x10, x25 and x100
Suggestion: wouldn't it be nice if when you upgrade your pirate ship to a aircraft carrier, especialy in water maps, that you could put another tower(s) on it.
:-)