Just anecdotal, but my S24 has diverse academic interests and is open to exploration, so he kinda built his list around flexibility (except St Andrews, but then that is why he scratched St Andrews). William & Mary made his list for just that reason, and I still think it would have been great for him. But he chose WUSTL, which I am sure is also going to be great for him, and in part that was just because it is in a nice, convenient neighborhood in St Louis.
But still, William & Mary was very tempting. And actually, the possibility of convenient beach trips was a significant pro.
I also note Gettysburg was one of the PA colleges I had in mind when talking about Greater DC Area colleges. It is really quite close to DC (and Baltimore), and you can tell from what a lot of kids there do.
I don’t have any personal experience with UPenn. They have solid programs in all of your areas of interest; but there’s no CS major or minor in arts & sciences, so you’d be spanning A&S and engineering. There’s a data science minor in A&S, though.
I know that structured dual-degree programs across engineering and A&S exist (case in point: CS + Cognitive Science)… but I’m not familiar with how feasible it is to assemble such a pathway on your own.
Re: William and Mary - if you’re considering applying there for IR, this is also one of the majors offered through their joint degree program with St. Andrews. This could be an additional enhancement on the IR side, but could limit the amount of time you could devote to CS/DS. Still might be worth considering, though.