Did anyone else get a "yay, suicide!" vibe from the book? Because, yes, there's a very odd take on death and being willing to die, IMO. (And how bizarre that the Ravenclaw and Slytherin ghost mascots were a murder/suicide pair? No hope for those houses, apparently.)

I think you've hit the nail on the head with this:

Frodo there is agreeing not just to probably die, but to fail...

There wasn't a sense at all that in sacrificing himself Harry might screw everything up. It was just, if I die we win, so I'll go die now. It was frankly, hard for me to read as all that sacrifical in the end. Especially as Harry was surrounded by all his beloved dead as he headed off to be killed.