[Schwag]

I'm not going to look at your list. If you want a reliable 380 fps gun, get systema oilless bushings(NOT bearings), bearing spring guide, ported piston head, gears, spring and motor. Get the deepfire all titanium tooth piston.
It's hard to go wrong with systema. The more different manufacturers you use, the more likely you are to have compatibility issues.

Some guys recommend tight bores, I find them overrated.

Have a pro do it, not a hobbyist and then take care of your gun.

There is no real average lifetime for an aeg. It's like a car, the more you use it, the faster it dies.