Welcome to the board.
I'm one of the few with a NA and it's a FWD at that. Don't underestimate the NA though, there are a few true rally cars around here that are NA. I've also killed my fair share of other cars out on the roads, lost a few too of course but it's the fun that counts

. There isn't a whole lot we can do for extra power as others have mentioned. My baby came with a Diamond and that's the only engine mod have for more power. Over spring break I might do the snorkusectumy but I kinda like the nice quiet exhuast, but then again.... I do have the AC system removed and the weight loss made a noticable difference in acceleration and even more noticable difference in handling and how she slides. I usually don't run with more than 1/2 tank of gas either because I can feel the weight of a full tank slowing me down (that and I'm a poor college student...) No one has mentioned seafoaming your engine yet so I will, seafoam it. Some have noticed a difference, others haven't, depends on how dirty the inside of the engine is to start with I feel. Personally I noticed that it pulls through the RPM range smoother after the seafoam and my idle definately dropped a couple hundred.
First thing I would suggest though is get yourself a good set of tires. I upgraded to turbo rims and run 205/60 and talk about a difference over the old 185/70/14's. A lot of people run wrx rims but personally I like my 15's because I have more tire sidewall and I probably use my Subaru as 4-wheeler up in the mountains more than some of the others here. Irregardless of your rim size, get decent rubber, all the suspension in the world won't do squat if you can't stick to the road

. There is a plethra of information on tires if you do a search and we're relatively nice people so feel free to ask all the questions you want and we'll either answer them or send you in the right direction. Drive safe and welcome again.
Lee