Tweaking the DOOR is a bit different from tweaking the window. Leaking door gaskets is one thing; leaking window gaskets is another. The OP talked about leaking WINDOWS, not leaking doors.
I still say window leaks should be taken care of by the door drains. Leaning door gaskets is another matter entirely.
Slamming doors is never a good idea. My father insists on slamming the doors on his (and my) car. It’s annoying as hell. There is no reason to slam the door on a modern car. The force with which you close the door has no relation to the security of its closure.