It'll add weight, but should help with the street legal side of things.
Awesome build!! Where did you get the 4 link kit if you don't mind telling
If you're going to do something like road course, or autocross for fun, that'd be the only reason to go with a conventional vacuum brake booster. They're quicker.
And hydroboost really doesn't weigh that much.
Sweet build!
Unlikely I'll do anything but groceries and drag strip.