Most Helpful Girl
The Doctor is an alien that does not follow the same gender binary humans do. So I think it's nice. People have been pushing for this for longer than you or me have been alive so.
Personally Steven Moffat has been garbage as the showrunner and made Doctor Who such a chore to watch these days so I'm mostly excited that he's finally getting the boot. Especially since he's being replaced by the guy who made Broadchurch and I really liked Broadchurch. Though I do wish we'd gotten a couple non Moffat-led eps with 12. Peter Capaldi is a genuinely amazing actor (watch the Torchwood episode he was in to see what I mean) but a great actor can't save shitty scripts.
Most Helpful Guy
No problem, but I think it's the wrong time and the wrong actress