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

That leakdown number is obviously concerning. Post compression test numbers too.

With that kind of leakage it narrows things down. Ask "what could it be?"

1. Something with the valve sealing
2. Something with the ring sealing
3. Something with the head sealing

Based on the deteriorating idle...my bet right now would be blown head gasket. Just a guess though.
If I recall the compression numbers were somewhere in the 125-130psi range, but on cylinder 4 it was down to almost 100. This is a factory low compression build with 65cc heads, thin head gaskets, and an Oregon regrind cam with 230/236 duration at .050" and just under 9:1 compression. Definitely wouldn't get the same numbers now doing a cold test.

Its looking like I really don't have a choice but to start taking this thing apart...Just sucks not knowing what exactly to look for really.