Meh - I'd rather have the 767 over the 75S any day whether traveling alone or not (but especially if traveling alone). Even if traveling with my fiancee I prefer having the aisle access provided by the 767 so that if she's sleeping I don't have to find my way over her to get out.
On the 75S, I think the faux leather on the seats gets hot and the last time I flew them on JFK - SFO the foot rest was completely worn down to the point of being uncomfortable by the end though I also flew on one early this year RDU - ATL (which was coming off of CDG - RDU) and it seemed to be in a little better shape though that was only a 1.25 hour flight.
They are perfectly fine and definitely much better than being stuck in the back (75S is the worst TATL ride in Y because of the 3-3 vs. the 2-3-2 you get on the 767 and A330s). The screen on the 75S are better than on the other planes which is nice - and it's not like its worth connecting just to avoid. Just would prefer a 767 or A330 over 75S if I had the option (but that option doesn't exist on JFK - ARN and JFK - CPH so it's irrelevant).
On the 75S, I recommend getting the bulkhead - extra room for your feet. 1A and 1B are the best option, 1C and 1D are a little more exposed to the front galley lights though still not a huge deal especially if you have a mask you wear.