Recent 789 experience was as follows:

Row 3 is pretty good - not too close to either of the J gallies/lavs, sufficient E baby separation. Footwells are indeed tight, especailly 3A/L.

Row 6 was only used by FAs to stage water - mostly carts were used for snacks, and wine was kept in the gallies proper. However, the minicabin is way too close to E for my taste if there are babies registering their displeasure with long-haul air travel. Engine noise is considerable as compared to the forward cabin, but I don’t mind/actually find it somewhat comforting (sadly, not sufficient to drown out aforementioned devil babies).

As an aside...

A couple of noteable exceptions, but mostly the crew working these cabins are as surly as ever. UA will never, ever be able to establish a foothold in the luxury market, regardless of whatever marketing gimmicks they may dream up. This recent MEL adventure should hopefully be the last time I ever redeem a six-figure balance of miles only to suffer at the hands of {FAs} with huge chips on their considerable shoulders; all parter bookings from here on out if I can possibly help it...