Ironically, Pitt had an ideal spot in Oakland... The spot where they built a baseball, softball and soccer field. Perfect. Awesome view of campus and downtown. If anything, I'd move half or most of that elsewhere in Oakland because it requires little/no room for spectators. And, then, put the same stadium there.
If they ever build one it will be there. It always seemed the logical place to me. It's cleared land ready for a stadium, and you can move baseball / softball behind cost. Soccer can play in the football stadium so you don't need that field anymore. Those facilities will need upgraded anyway in another 10 years. Any forethought by the university and they considered this already.