Fuji body, (I like Xpro2) with CV Nokton 35 1.4 is light and fast. That’s probably the smallest 50mm equivalent I’ve come up with if using modern optics. If you wanna go REALLY small, you could always find an OLD 35mm Elmar. That’s the tiniest lens I own but rarely use it.
For modern optics, the 35mm f2 fuji is good enough for me.