Too long, but did skim. I won't weigh in on the letter except to say, I do agree with "Equal rights means equal risks" if for no other reason than I think that's the only way to get interesting stories with character of both sexes.
That said, equal risks means equal rights. If you have Batman have his back broken and come back a year later like nothing happened, you shouldn't (for any reason) make Batgirl wait twenty years. You can't take Dinah's Canary Cry away for ten~fifteen years when she gets tortured, and then have Ollie walk away from a similar situation with little more than a bruised ego.