My current opinion / standing on the over-clocking power issues is that I'll get the current version working fully and then do a version 2 board that uses the IR3847 buck reg chip instead. The circuit is almost identical and just has some position/orientation changes. The sourcing may be more difficult but it's still the better choice for boosting the on-board power without too much redesign. Most of the parts are value changes to similar parts. I think the main issue will be the Cyntec 0.215 uH inductor (PCDC1008-R215EMO) and for those looking at sourcing and supply I'd start digging into how to get test samples and place larger orders of that part. It doesn't seem to be commonly available at Mouser/Digikey et al.

Just some forward looking comments at this point.

On the K1 it's possible to replace the 6502A with the 6503A and use a powered hub to get up to 3A of juice for the ASIC over-clocking. It's almost the same price anyway but would require a small bump in inductor choice.