Just fitting it won't raise boost on it's own, no. You'll need to set it up to the boost you want to raise it too ! :lol:
It should be fine but, make sure the rest of the engine, ignition and fueling are in good order. You're best bet is to get it on some rollers and get them to check ignition and fuelling when you've set it to your desired boost level !
All the things you have mentioned will help performance though. The exhaust in particular, should help spool up (not so much without an enlarged elbow and decat) and release some extra ponies and torques !! :lol: