oooooh, YES. Absolutely. And Martha standing in Rose's shadow fits, too.

Also, omg, the idea of Jack Harkness getting anywhere near the One Ring is frankly horrifying. I'd like to think he'd have the Aragorn-like common sense not to touch it with a bargepole, buuuut that depends on where in his timeline you fall I guess.

(Still pondering Donna and Mickey's respective roles in this, hmm.)