Tidy looking car.
May well be nothing wrong with the intercooler - just clean up the front and if you are worried, pressure test it.
Incremental mods tend to be a waste of time.
If you want it to go faster look in the RB25 turbo upgrade thread and see how much power you want.
Then open a special bank account and save up the $5k or $8k or whatever depending on what you have decided and do it in one hit.