[Krsqk]

I don't think #1 is possible. Sorry. The only way to really help is to fire on the planet to remove weapons platforms before landing troops--your troop transports tend to have a longer lifespan when not under fire.

For #2, you could mod your 400kt fighters, then mod all weapons to fire on fighters (the latest patch made that a lot easier), then add a defensive bonus to regular fighters (to keep weapons like massive-mounted IBs from mowing down thousands of fighters at a time). Since fighters already are cannon fodder, the extra defensive bonus wouldn't hurt. There (unfortunately) isn't any way to implement true system ships--it was planned from the beginning, judging by the data files, but never made it in. There's always SEV, though.