"Well, I know that different things are going to happen to different future versions of me across the many worlds."

From what I understand, the many-worlds occur due to subatomic processes; while we're certain to find billions of examples along the evolutionary chain that went A or B due to random-decaying-netronium-thing (most if not all of which will alter the present day), contemporary history will likely remain unchanged; for there to be multiple future-histories where the Nazis won (not Godwin's law!), there'd have to be trillions of possible realities, each of which is differentiated by a reaction here on earth; and even if these trillions do exist, then it still won't matter for the small subset in which I exist.

The googleplex of selves which exist down all of these lines will be nearly identical; the largest difference will will be that one set had a microwave 'ping' a split-second earlier than the other.

I don't know that two googleplexes of these are inherently better than a single googleplex.

As for coma - is it immediate, spontaneous coma, with no probability of ressurection? If so, then it's basically equivalent to painless death.