Aero gains >> weight in almost all circumstances. If my google-fu is right, your Roval Rapides have a depth of 51 mm and 60 mm front and rear. The Firecrests would be pretty close to that, and I am not sure if that’s really worth it from that angle.
As far as tires are concerned, I’d just run 28 mm tubeless all year round. In fact, I do 