With those types of cameras, you CAN add lenses on to them later, but for now just worry about the body itself. If you find you want one thing or another (wide angle, fisheye, longer tele) then you can look at add on lenses later for what you find lacking.
As for video performance, for sports 15fps is a bit slow, but when I shot clips with one of these I never noticed it being choppy. With my dslr I shoot at 24 pretty much all the time, I like the way it looks better with the slower fps.
Honestly, silly as this might sound to some, if I you care about pics & hope to learn, I can't imagine getting a camera without a hotshoe. Lighting is one of the biggest learning curves in the game, get started early. With the G you can even shoot with wireless flash & have the strobe sitting under the subject. I've got 6+fps on my 7, but if you're shooting with flash it doesn't matter. (btw, it's 1.5fps, not 2 sec per frame)
A shot I took at crankwerx a couple weeks ago to show the setup, you can run wireless in the same way with this.