I don't see why a UConn / Princeton matchup would be good for anyone.
For UConn, just another blow-out. For Princeton, a non-winnable game. Sorry, Princeton is not at a UConn level (who is?). And this is one of the times you can just toss RPI out, it is meaningless.
Their prime candidates are playing decent P5 teams. They might very well have been able to beat some of the teams seeded ahead of them, probably up to the 3 seed line, even, in the right circumstances. The top teams, not so much, and not much to be gained from trying. They need to show they can compete (win or lose) at a higher level, not just play and get blown out.
If you are saying that Princeton's "prime candidates" for future-year schedules are P5 teams who were 3 and 4 seeds in this year's tournament, then I agree that those are teams that Princeton should play, and it would be in Princeton's interest to schedule them. I suspect Ms. Banghart understands that completely, and has probably tried to do that.
The problem is that those teams are unlikely to sign up for a Princeton game, because (gasp) Princeton might actually beat them. Then they would have to deal with a "bad loss" to an Ivy League team. Those teams believe that they get all the SOS and RPI they need from their conference schedule, so what they need from their non-conference schedule is the maximum number of W's. Unfortunately, the raw number of wins (never mind against whom) still counts, particularly if you are playing good teams in your conference. It doesn't help as much if you are Princeton or for that matter UConn, since they face very few good opponents in their conference schedule.
That is why I think a UConn-Princeton game makes a certain amount of sense for both. It would be a better game that either team will get in its conference. It would also be a better opponent than they can easily find out of conference. It would be better for UConn if it could schedule Top 15 teams for its OOC schedule, but that appears to be increasingly difficult. (Of course, this year Princeton was a Top 15 team by the end of the season.)
For Princeton, it might be possible to stay within 20 points of UConn, as St. John and USF were able to do. That would be a major triumph for their program, and might actually help with the NCAA Selection Committee's "eye test". And presumably they would learn something about basketball, see some plays or defenses that they might use against other opponents, deal with a big and partisan crowd, and possibly get an ESPN audience (and some moolah) for their recruiting. Not a bad deal, overall.