What phases would you like to see done?
Here's mine.
Phase I: West side expansion. Press box renovation, Stadium Club expansion, covered seating expansion, Balch destruction or renovation. Add 200 level seating where we don't have it and do a full 200 level like on the East side.
Phase 2: End zone expansion. Enclose the North end zone with a full sized 200 level included. Increase the South end zone seats to the full 200 level height that's in the rest of the stadium.
Phase 3: Club level expansion. Add Club level seating above all 200 level seats in the stadium. This one might have to happen in sub-phases.
I don't know if this gets us to 80k+, but it definitely gets us over 70k without ruining views or the existing character & feel of Folsom (Frontier?). It also adds a lot of high revenue seats in the process.