When will Democrats win back the House?

[Skill and Chance]

Well, there are really two ways this can happen:

1. Geographic realignment where Democrats either recover to >40% with rural voters or start winning inner suburbs 60/40 and pulling to a tie in the exurbs.

2. A Democratic wave with ~57D/41R generic ballot

Caution is warranted with the comparisons to 1933-1994 having 4 years of GOP control.  While that is technically true, ideological conservatives clearly held the balance of power from 1939-58 and during 1981-82.  With today's ideologically polarized parties, the equivalent would be Republican control about 2/3rds of the time until the mid 2050's, which sounds very believable to me. 

[Skill and Chance]

Sometime in the 2030s in the worst-case scenario. It's increasingly evident 1994 was a realignment.

Yeah, the case for 1992-94 being the realignment is now much stronger than for 2006/2008/2010.