Or have Lippy only move SK cards back into the deck if the idea is that he resurrects all the fallen comrades. That way Lippy players get to replay Cerys and what not but don't get a 2nd heatwave, Roach, Knickers, CoC, Snowdrop etc. Limiting interaction to faction cards is what we saw when they changed Caranthir and Queen Adalia so why not give Lippy the same treatment
The leader should stay as it is because it will only hurt other decks that want to use that leader when the change is only supposed to target the current Lippy deck anyway. What I mean is that I think a leader change is way less likely to be reverted back or changed again, so before they tamper with a leader ability I'd rather have them look what card interaction could or should be addressed.