Well thats my view anyway
I think your running to much pressure in the cylinder head making it burn oil out the catch can.
If you wanna strip apart the block and spend loads first go for it.
But in my view start with the simple cheaper things and go from there.
Good compression and ok results from leak down would make me look at alternative solutions.
A cheap catch can prob doesnt help.
Dont some people run one line to catch can and one to vent?