Upgrading airguns in general is fun and rewarding but, the end game is still a low-end pcp that costs as much as a mid to high-end pcp. If you want accuracy and performance at a reasonable price, AEA is a very good option.
You should be able to get 850-880 fps out of the 35 gr without too much difficulty. A power plenum and slug probe would make this even easier. I hope this helps. Good shooting.