The state I'm watching is Florida. A court-appointed special master's map there might be the biggest boon for the Democrats this cycle.
Unfortunately it looks like the GOP obeyed the new law just enough to avoid the map getting tossed. Granted in doing so they gave the Dems a new seat and threw an already in rough waters GOP incumbent under the bus and left a few seats potentially competitive they could've changed. The real point of contention is the Tampa Bay-St. Petersburg area mess where there's still good lawsuit potential, but I have a feeling any redraws would be just around there instead of the whole map. But if it's enough to scare Bill Young into retirement and result in a Dem-leaning open seat, I'll take it.
Texas looks like a potential court-draw though.