If only I would have the patience to hand-craft large graphics, I'd make my own suggestions for some of the guard posts and guardians, but I'm only really good at tiny sprites and fiddling with colours. xP Small starships is pretty much where my patience ends, size-wise.
From my expereince wiht Arcen, making your own graphics and donating it can get them in the game if you feel it is better then originals (I happen to suck at graphics and never do it )
Yup, those be my flak turrets and heavy beam cannons in the game. I'm already honored to have 'em included.