Need some opinions on where to go from here...

Yea I agree...I guess last night I was just sitting there a bit annoyed that I haven't found something more obvious at this point. Next time I'm out in the shop the heads are coming off and I'm getting them to a machine shop for an inspection.
It's winter. We've all had builds go sour for one reason or another...

Be patient, inspect, and be diligent with your cylinder bore to piston clearance measurements. Check the ring lands on your pistons.

You may only be in the solution a set of rings, some gaskets and a couple hundred bucks of cylinder head work.