1.5 or 1.6 roller rockers.

I like the 1.6 here. Your valve lash is losing some lift at .014, plus the pushrod angle isn't dead on either, so that loses a little more. Not as bad as a small block, but there is some loss. Plus there's a little power to be had. Nothing complicated about it, either.
Agree w/ this.-I`ve got a one step hotter solid roller w/ 1/6`s on it.