I've tried a number of binoculars (Zeiss, Swarovski, Leica, Steiner, Kowa, Kamakura, Nikon, Meopta) in the last week and think Kowa Prominar 8.5x44 XD has the best optics of all. This is because the color is neutral and that it handle chromatic aberration in a very good way. Unfortunately it weighs a lot ..
However, I prioritize good optics in front of a lighter design. But the question is..do you have any tips for avoiding neck pain after a day of bird watching with a heavy pair of binoculars?
Use a harness not a neck strap. No more neck pain!
Of course the downside is perhaps the geeky look (but then again I don't care) and the difficultly in shedding or adding layers. If it's not too cold then I mitigate that by wearing the harness under my jacket with the jacket a little open (and you can fully open the jacket to cool off). Not an option in perhaps for a Swedish winter (but then again keeping wrapped up might be the right idea).
You're right, heavy glasses are a pain in the neck. I've made an extra-wide leather strap and try to wear outer clothes with thick collars to put the strap behind, to give my neck some padding.
My best pair are Nikon HGs (the older, heavyweight ones) and on a walk of anything more than a couple of hours I substitute them for a lighter pair. The weight is a real problem.