Yes, I wouldn't overthink it, you are supposed to be asleep here! There again I'm amazed at the effort some people put into seat selection. 11A and K would be my fallback if 5A / K wasn't taken. It is noisier, definitely, but there is relatively little footfall there, the crew rarely move between CW and WTP-WT. The bassinet for WTP is right there, so theoretically noise from any toddler, though I seem to manage to avoid that on the whole. So for me it is a second best, but with some advantages. 11K is handy for the WC, 11A for Club Kitchen.

If LGW, consider the risk of an equipment change for the next few months until the fleet gets sorted out.