I think the consensus among DL regulars is that the 739 is a really bad FC experience ... the 757 has the same seats, but (a) you generally board thru the 2L door which minimizes the pre-departure parade of all the coach pax (hence increasing the likelihood that you can get your pre-departure Woodford or other beverage of choice), and (b) the FC lav hasn't been miniaturized
I think the consensus among AA regulars is that the ex-US 321s are rather more bare-bones than the AA birds (32B) in terms of configuration and amenities; AA is also reportedly very inconsistent in terms of pre-departure beverage service