That pic is probably of the prototype or very early (non-released) production model. I have seen quite a few in person, and a few friends have them, none of them came with pullstarts.
Whenever you trash a one-way bearing, you should also replace the one-way shaft. If it gets scratched or scored, it'll trash the oneway bearing.
I've got almost a gallon through my savage and violator, with absolutely no problems. Everyone I know that knows how to maintain and operate RC's has not had problems. You might want to get together with some veteran RC guys that run savages and see what they're doing different than you.
If your backplate is leaking, you need to take it off, clean it up, and put it back on with blue loctite on the screws. If fuel is getting out, air is getting in, it is probably causing you some tuning issues. Consider putting a tiny silicone bead around it to further seal it.