As an employee of the MC I can tell you that they will not be building a new MC for at least 40 years. It was built to last about 40 years so when that came around they reviewed it and decided it was in such good condition that they wanted to make it last another 40. Thus the multi million dollar seismic upgrade, expanding the concourses, new seats, new locker rooms, new jumbotron (soon).

With regards to the practice facility, they originally wanted to put it just north of the MC where that house got hit by the car. BYU owns the other house on the corner. Most recent update that I heard from my boss is that they are considering putting it in between the MC and the broadcasting building and I assume it would be attached to the MC in that case. All speculation at this point though