You never said porting the heads in your post, you listed intake tgv's and throttle body..... porting the exhaust is WAYYYY more beneficial than those.
edit: I'm wrong, i just saw cylinder heads.... I actually must have had selective reading when I read your post LOL because I skipped RIGHT over it
We're talking a couple hundred dollars to pay some one to port all of those things... bringing in head work bumps another zero into the equation, which not a lot of people have the money to just go out and port/polish their heads.
And porting the ex. manifold doesn't do much for peak or top end.... so don't count on 30whp, like mentioned above the gains are the better bottom end and boost response.