You are correct. The 75's generally go as follows based on F config:

16 F = Business Elite (75E or 75A)The 75E's have in seat entertainment at every seat, the 75A's have portable DigEPlayer things for J, but overhead in Y. 75E's have power in all J seats and some Y seats. I don't know about 75A's, but I believe they all have power in J.

20 F = Slightly nicer domestic first (ex-NWA interport aircraft, 75J I believe) I don't know if these have overhead TV's or not. Don't know about power on these either.

22 F = Many different variants. There are the 4 HI 757's which have leg rests and tons of leg room and there are both the ex-NWA domestic 757's (5500 & 5600 series). They are both standard old NW domestic F. The HI birds have overhead entertainment, but (correct me if I'm wrong), neither of the NW varieties do. The HI birds had power last time I was on one, but the NW birds don't.

24 F = Standard old DL domestic F with overhead entertainment. No power.

26 F = Ex-song birds with new F. These have In seat IFE as well as power. (75X).

Hope that helps.