Here is my Princeton breakdown: looks to be holding well, including calling their freshman really good despite him having a 7 ERA last year:
Princeton returns their closer (Jacob Faulkner), who is a command specialist who gets tons of ground balls. He was their closer, but he actually led them in innings pitched by a large margin. I'm not sure if they'll convert him to be their Friday guy or if they like using him as a multi-inning reliever who can win a game late. His advanced metrics say he was a little fortunate on balls in play, but overall his numbers were legitimate.
Their top starter last year was a freshman who had a really poor ERA, but underlying metrics say he was pretty good and he was terribly unlucky on not just balls in play, but his strand rate was comically low.
One of their best arms (Justin Kim) started the season well and then got hurt and missed the rest of the year. I don't know his status for this weekend, but I'd doubt he will be ready.
They return most of their pitching staff and rotation, but they were fairly meh on the mound after those two above, and the relievers were downright pitiful last year with a major propensity for walks.
Princeton returns seven of their nine starters on offense, losing their second best hitter to Wake Forest and one of their power sources to Duke, but he actually lost his job to another player and was moved to DH, so the loss is lessened there.
As is typical of the Ivy League, they bring in no new transfers, only freshmen. None of their freshmen are especially well-regarded.
Because of this club being more experienced and much better defensively than Niagara, they will present more challenges. Their best player is All-Ivy League 2B Jake Koonin.
Picked fourth in the Ivy, their best chance at a win is to have Faulkner come in with a lead and go 3-4 IP to close one out.
Miami should have a few games where they blow up the scoreboard, one game they win pretty easily, and one game that is contested. Princeton is a better team this year than last year according to my model and they won a game against UNC-Wilmington (a strong mid-major program) to start last season, so I wouldn't get overly preoccupied with the amount of time they've practiced outside or not.
If Miami does not score runs on this bullpen outside of Faulkner, we should be highly concerned for the season. They're one of the worst bullpens outside of Faulkner in my model.
Expect Princeton to finish in the mid-200's this season.