Lexperting...

10k 7s: 2930 still unsolved on 2nd run.

10k 8s: 1466 unsolved/6370 on the list (slight improvement over the 7s at the same stage, 1st run)

Next lists:
4-7 JKQXZ
4s (3rd run)
5s
20k 7s

very ambitious undertaking, but i don't feel confident