Again, don't get me wrong, I love RuthDoc, but outside of Colin with Pat has any Doctor ever been shunted into this position this early? (in fairness I guess Tennant had Sarah Jane pop up three episodes in)
Yeah, but I don't think that was ever a problem with Tennant. Tennant totally had me sold from, "New teeth. That's weird."
And Colin Baker has much worse problems than a multi-Doctor story where Troughton spends most of it captured & drugged. (Ugly costume. Shrill, obnoxious companion. Shitty scripts.)
Yes, many (including myself) have said that we could have had the Eighth Doctor in Day of the Doctor instead of the War Doctor and it would have worked just fine, and that is true.
I don't know about that. Part of the reason for the John Hurt Doctor was to have an older Doctor that spiritually represented the older Doctors from the classic series. Much as I love McGann, he wouldn't have provided that kind of stark contrast with the fun bounciness of Tennant & Smith.
As for Whittaker, I think she's doing fine. She's by far the best thing about her run and the only thing holding the show together, IMO. Jo Martin seemed fine but didn't leave too much of an impression on me. Granted, I'm too busy trying to figure out what she is to focus on her performance very much.
BTW, I don't think that she's a pre-Hartnell Doctor. As I've heard other people note, Hartnell's TARDIS didn't start looking like a Police Box until he landed in that 1960s junkyard in "An Unearthly Child." If she's part of the regular sequence of Doctors, she's more likely from Season 6B, between Troughton & Pertwee. But given how shocked that Gat was, I think it's more likely that there's some alternate timeline shenanigans going on, with parallel universes bleeding into each other.