I've flown the 727/737/A319/320/A310/A300, not in that order(plus a few other non A or B products). Looking back on it, the 737 is the one I miss the least. I agree that Airbus cockpits are quieter, more comfortable, and in general have more logical ergonomic features although some A310/A300 operators didn't consider a cupholder a necessary feature. While I absolutely love the classic Beast-727 and you won't find me saying anything bad about it, I've preferred the Airbus planes I've flown overall. Basically if you could give me an A320 with as much power as an A300, I'd be quite happy. Same thing for an A300/310 with a retrofitted A320 series style cockpit like they're doing with the 757/767's(plus cupholders!). Nothing is perfect, Airbus, Boeing or whomever, but I really love ECAM. I like coming into the cockpit and not being inundated with a bunch of yellow and red lights/messages on the screens. No messages about low oil pressure, low fuel pressure, low hydraulic pressure, etc because the engines are off. Basically if something on the screen isn't green check it out. I've found it easier to find glaring issues on setup quickly vs wading through a flow to find them or playing guess which one of the six pack lights shouldn't be on now, or which one of the 3 pages of EICAS messages isn't right. There are exceptions to the rule as nature abhors a vacuum, but it's overall a big plus for me along with the obvious ECAM checklist stuff.
As for the flying stuff, I've never really gotten into all the drama. They're both airplanes, they both fly just fine, and like different airplanes they fly differently. All of them will erode your skills if you allow them too. I know plenty of 727 pilots who flew with the A/P from about 800agl to 500agl on the way down and were pretty shaky skills wise if they had to do anything else. They probably had it years ago, but use it or lose always applies. I went from the 320/319 to the 727 and it was no big deal to me as I did a lot of hand flying (AT off as well) in the 319/320. I thought the non moving levers in the 319/320 would bug me, but they didn't. I had a pretty good idea of where the power was by feel/sound and the power lever doughnuts are there as well. Clicking everything off for a TCAS RA, quick leveloff, visual go-around, etc, I pretty much did like any other plane pulling the levers to where I felt they needed to be by feel then confirming with the gauges/speed tape/etc. Doing that a few times in the non-sim world really solidified it for me that I had a good idea of where the power was and it really wasn't an issue. Other than that most stuff seems minor to me. Boeings tend to take more rudder pedal travel to get the desired movement in a X-wind, which is no big deal as long as you realize what kind of plane you're in. Airbus medium autobrakes blow compared to Brakes 3 on a Boeing, I don't know if they fixed it in later planes or not but it seems to be an Airbus trademark. As for the rudder stuff, I also disagree with the poster that said that we weren't warned about the sensitivity of the surface at different speeds and the potential for structural damage. I know I was told about it in training at least 13-14 years ago and told that certain carriers were emphasizing training that was a bit too aggressive in their opinion.
In the end, I prefer the Buses a bit more, but you could plop me in a 757 or a 777 tomorrow and you probably wouldn't hear much out of me other than complaints about cockpit noise or relative comfort(757 not 777). I'd miss some things, like some things, would fly the bird in front of me not my personal idea of how things 'should' be, and enjoy myself which I'm sure you will whatever AA purchases. If you put me back in a 737, it'd be a different story though.....
