I've always been a little unhappy about the size of the ground pads on the u.FL footprint, I think if you can remove 8-10 mil off the highlighted edge of the ground pad (you can actually do it to both ground pads), without moving the center of the part, it will improve the clearance between the 50Ohm trace and ground.
This makes the line less lossy.
From @andyw-lala
Check out the attached image.
I've always been a little unhappy about the size of the ground pads on the u.FL footprint, I think if you can remove 8-10 mil off the highlighted edge of the ground pad (you can actually do it to both ground pads), without moving the center of the part, it will improve the clearance between the 50Ohm trace and ground. This makes the line less lossy.