Well I suppose if you guys have not had bad experiences with larger lines, it can't hurt. My reasoning was that the default wastegate signal came off the turbo compressor, so there was no more than about 8 inches of vac line. Now, using vac signal off the intake manifold, the line needs to be about 2 1/2 feet long, so I ran super small vac line to keep that total internal volume down...
-Ryan

I only need two settings, three is rather pointless to me, and never want to run near wastegate level - this wastegate is about 6 psi, and being the TD04H there aren't a million aftermarket wastegates available like there are for the Garett series. Plus, the wastegate is trash, I always want a boost controller doing the actual work.
I'm looking to do an 8-9 psi track boost level and a 14 psi street/autox level.

Vac line diameter is not a huge deal. You're right, smaller diameter results in quicker changes, but it's not a huge deal. I always use 3/16" or 1/4" line. It works just fine.

As for EBC, I think for $7 you should buy the add on board for MS and play with it. It's cheap so there is no reason not to try it. With it, you can vary boost by rpm(so you can broaden your torque curve) and in the future(if not right now) boost by gear. Overall, $7 is a cheap investment. Even if it sits in your desk, it's worth the money.

MS1 EBC is trash, there's no reason to even try it.

I didn't see him reference his system in the post. I assumed he was using MS2

DIYPNP Megasquirt is MSI I believe? I haven't converted anything, and have been adequately happy with everything the existing setup has to offer. I know there are benefits to MSII but most of them are things I would not take advantage of anyways. I do not want EBC for example.