Joe, that's illogical. An important part of a good game is keeping fans hooked. If they wanted to keep everybody, they wouldn't stop updating SSL2. They probably released the steam version for people who have steam. And if they don't, they can still play the Flash version.
Idea: Special options for the game, such as Low-Grav, All-Walls (in which the shots can not escape the screen), and Light Tanks (tanks move faster, but are affected by wind every turn)
2/5. The enemies, as said above, scale way too fast, and you might want to scale the base of any exponential function down. It ruins the point of the game.
When you get a watermill quest and realize that the nearest source of water is 4 tiles away, you gotta ask yourself, "Where the crap are these monkeys getting their water!?"
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