which branch of AME is best for future and which branch provides more salary
Both are good whether it is Avionics or Mechanical. But if you consider job Opportunities then Mechanical's have a slight edge as compare to avionics,
In mechanical stream you can learn everything more easily, because you got enough foundation from your plus two physics and maths while in avionics you will have to mug up various things like complex Electrical Ckts, their diagram and various other things.
All the best!!!