Were you in NYC? We may have crossed paths since I was doing some watch window shopping as well.
I went to the Omega boutique first to check out the Seamaster 300 Master Co-Axial. I will preface this by saying that I'm a dress watch guy and don't own any divers, butwoukdlike a nice waterproof watch for the beach. I really liked the Seamaster, but as you say the thickness was a real sticking point. The dial is great and surprisingly I preferred the look of the black dial to the blue. I thought I'd be put off by the dial size but it looked great. I wasn't a fan of the polished center links on the bracelet, and as you say the watch is so thick. I'm not sure I could pull it off. Maybe I'm not meant for dive watches.
Then I went to Wempe for some general browsing. I looked at some Tudor Black Bays but the dial didn't wow me nearly as much as the Seamaster. Then I saw a Sub no date. It is very competent. Looks-wise it's a 7/10 compared to the Seamaster but there are no real flaws to it and I guess there is a reason it's considered the dive watch standard. Not sure I like it enough to buy it though.
Then I went to the JLC to check out Reversos. They are doing away with the previous sizing system, at least for men. Now, the standard Reverso will comin in small, medium (similar in size to The Grand Taille case) and large. The small is quartz, and the medium and large are automatic (yuck!) The seconds hand is gone. I'm not a fan of these changes, and I think I'd look for a used Grand Taille in steel or Sun Moon if I wanted a fancier watch.