Looks like youre doing everything right. Giving her lot of out of cage time to fly around will help keep her fit, trim and healthy. Overweight, out of shape birds are at increased risk for egg binding, and it's a horrible way to die. If you you worry about too much fat in eggs you can always just give the white, but the yolk is loaded with nutrients.
My favorite budgie, Rocky, is laying eggs right now and I wish she wouldn't but there's not much I can do. She lays them in various places and I take them away. Yesterday she laid one on top of the cage and it had a bit of blood on it so it must of hurt! She lives with my mixed sex flock of 9 that fly free in the room all day and is strongly bonded to a particular male who's the egg daddy. I love my girl birds but sometimes I wish they were all males because egg laying often becomes a problem.