Here is a suggestion:
Have a site in each area (upstate, midlands, lower state).
Rotate the locations.
Play uperstate/lowerstate final at 2 sites and the final at the third (i.e. US at Clemson, LS at Blackbaud, Final at USC/Irmo/etc.) the next year US at USC/Irmo/etc, LS at Blackbaud, final at Clemson.
Rotate every year.
Not only should the final be a neutral site, really so should semi. This would allow for 3 or 6 year contract and would make transportation easy since you know where you are going.
Why should semi be played at an arbitrary "home" field based on a horrible bracket?