Technical Aftermarket PCV

Have a 2 pc rocker cover filter. Right now it has foam ring insert and very small ID fitting. Should I make ID larger and use paper filter for better flow?

 

So very little info. What's it doing/not doing? appears to be a breather w/foam filter. What is "very small id" ? Does the other valve cover have an actual pcv installed? There are numerous threads here in re: PCV operation

 

Also what engine is it going on?

 

What you are showing us in your photos is a "breather" and not typically part of a "PCV" system.
What's missing from your photos is a Positive Crankcase Ventilation valve, which is a small canister containing a spring and ball arrangement that can block flow, allow flow, and every degree of flow in between, depending on the condition needed at the moment.
Back in the old days, when all the old HAMBsters here were still virgins, "breathers" or a simple "dump pipe" were used to allow the crankcase blow-by to escape into the environment so that pressure didn't build up and start blowing gaskets. This was effective at relieving pressure but was highly polluting. In these times of running a sealed PCV system, a breather may be used to allow some filtered fresh air into the crankcase for the occasional condition when the intake manifold vacuum may be attempting to pull more blow-by vapors than are actually being produced in the crankcase.
What is in your photos looks like a hybrid, not quite a simple breather or exactly a sealed PCV system. Maybe call it sort'a clean, sort'a dirty. But to answer your original question, no....... there's no reason to enlarge or modify any of the multiple small holes in the aluminum piece.
You may have a PCV valve somewhere not shown in your photos. A valve can be spliced into the hose anywhere, including at the other end of the hose where it dumps into the intake manifold. Without seeing the entirety of your plumbing we are left to only guess what is right or wrong with what you have.

 

I think what he showing is the suction side of the system to get air flow thru the engine to enter cleaned. The hose could go to the air cleaner. The rest, as said, would be the valve side and hose to the intake or carb vacuum.

 

. . . . . Crickets, I can't imagine posting here and then not checking or responding to replies for 3 weeks. Hell, I look in daily and lurk around just to see what's new.

 

What he said.