Could you make this the night before and reheat?

Yes, you can prepare this all the way through the baking step the night before. I would not worry at all about the pasta being too mushy, because the pasta is only cooked for 4 minutes before combining with the sauce and baking. In fact, I'd be concerned that the cooked dish might be too dry. To that end, I'd cover the dish tightly, while still hot, to trap in the moisture from the steam and to reduce its drying.

I've also found in similar situations that the pasta tends to soak up the sauce. For that reason, I would not cook the sauce down to thicken it as much as I would if baking it right away. ;o)