Agreed with the comments on the rotors. Mine did that too, for a while and one of my friends with an STi (please don't kill me for saying that) also went through the same.

As far as goals for any project go, just remember that once you start doing upgrades, the cost of the parts+labour is not the end of the story. Every mod you make is a potential point of failure, so you have to be ready to repair whatever it is you just modded (for example, if you get a standalone ecu and mess up the tuning...). I like to budget 50% over the cost of parts, labour and shipping (on average) "just in case". But that's just my 2 cents