Paging @clidgey to the red phone....
And if you're adding boost in a boost-limited class(at least with scca or most of the more competitive clubs), someone will know, especially if you're clearly faster than you should be.
Currently, there's a proposal within the SCCA to create a class for more DD hot hatch mods, and they're calling it STH. With the new class proposal, comes the availability for open boost and open tuning(but not replacing boost related components, i.e. hard pipes, IC, BOV, etc). So if you are a current SCCA member, I suggest reading the current Fastrack and submitting a letter of support, or if you see something you'd like changed, tell them your ideas.
I'm running HS this season(and probably next), but STH is definitely on my radar for an upcoming season.
As far as the tune, I'd ask some of the forum sponsors on here about it. (stratified, dhm, etc). I have a local that I trust with my tuning, so I'll be asking him if my need arises.