I like alot of your ideas vynce, mr.nick. I thinking most of the world actions will be 'hard' code into the game to avoid cheating. when I say hard coded I mean its not controled by the end users script.
I thinking a few weapon types might be better then just one. I was think along the lines of a cannon (1 shot, small area of damage, accurate) and a rocket (1 shot, large are of damage, inaccurate) and possibly a few others. This would also make team matchs interesting, you control 3 tanks and they can talk with each other, one tank with active radar one with pasive could make for some fun combos.

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The Price of Freedom is Eternal Vigilance