You said "light rifle", and I'd sure look to the 2.5x8 vice 3.5x10. The latter is significantly bigger, somewhat out of place on a smaller light rifle. If the difference between 8 and 10 power on the high end is important, something else is wrong.
You don't mention caliber, but you might also consider the 1.75x6. It is a terrific scope, excellent in low light, smaller profile (32mm). I have one on a fairly light 300 WM, don't feel disadvantaged one bit.
