Do special procedures exist to limit pilot workload during pilot incapacitation?
Well, as a catch-all there is always FAR 91.3 which says he pilot in command can deviate from any regulation if they deem necessary in time of emergency in order to safely operate and land the aircraft. Obviously there's a reasonable limit to that and you'll be asked to give a report to the FAA on what happened, so be ready to defend your actions.

I can't comment on airline company procedures, but I have to assume there is a plan in place for this scenario since it is so realistically likely to happen at some point. I believe another crew member would be asked to help with simple tasks like reading checklists as you mentioned.