I'm thinking you might be better off with some beefy front and rear aftermarket sway bars and endlinks instead of strut tower braces. Some of them are pretty stiff and they'd probably be more effective in reducing body roll. I think your stock rear endlinks might actually be plastic too - I'm pretty sure they are on 02-07s anyway and aftermarket endlinks are metal so that alone is a pretty big improvement. But, if you want strut tower braces too, they certainly wouldn't hurt...
07 WRX (Albins 5MT + Blouch 20G)
Jorge Carrillo Tuned (365 whp/340 wtq)