I was surprised how much difference the door seals I used made. The noise was reduced to roughly the same as the Leaf rather than being excessively loud which was one of my gripes when I first got the car.
The seals I got were somewhat custom.. different types of seal for different parts and a proper L shape for the door corners. The excess is just to avoid being too short accidentally I think. I didn't have to trim for drain holes - they weren't blocked.
I had similar mud flaps but they weren't flat on the front facing part, they were concave, which would introduce a lot of drag, so I decided not to fit them. Will look at that later on.
Not tried the roof seal.. I may do if it helps, but the videos I saw on it were inconclusive.