That is the same coil and wires I got and I set mine up using a relay also.
Your lengthy list includes almost everything a fellow should consider. If you get to the end and are curious about movement of your camshaft, here is one thing I discovered back when this happened to me: A timing light might answer your question. That is to say, the strobe light might show the needle on the bell housing is striking the mark on the flywheel before and after that mark.
Hopefully that makes sense. At idle, your centrifugal weights aren't kicking in. Or that is to say, they aren't doing much if anything at that speed. And if they're providing any increase in timing, it will be small and not fluctuating. Because your vacuum advance won't be doing anything at all at idle, the timing light should show the pointer lining up with the mark on the flywheel nicely. If it is bouncing all around (advanced, retarded, occasionally on the mark), your camshaft could be moving in/out.
I paint the needle with white paint and I make sure some timing line on the flywheel is a crisp white line. Also, maybe the 5* BTC line.
Just a thought.
