Not sure where you are going, or what equipment you will be using, but I have a wrecked shoulder as well. As noted above, quick releases on your BCD/harness are nice. For boat diving, your operator makes a difference as well. In Cozumel, "valet" diving is the standard. Your equipment is set up for your, they help you gear up, most boats are backroll entry so you never have the weight of your gear on your shoulder, and most exits after taking your gear off in the water and they lift it into the boat for you.
When I shore dive, (oklahoma muck style)my harness does a good job of distributing the weight for a walk. I worry about my knee more than my shoulder if I have to walk a "path of doom"
I've never been on a dive boat...ever...that any help that was needed was readily offered by either other divers or crew. I think the key will be to recognize your limitation, work that into your evaluation of any dive, and communicate with those around you and any op in advance that you might need some help. Advil is your friend....
Isnt getting old fun???
Good luck,
Jay