Indeed, Matt Smith held it together for a while but it was a slow decline in my book. never warmed to Capaldi I'm afraid. Tennant IS a class act in whatever he does and is difficult to follow.
I think that the new writer will have much to offer, if you have seen Broadchuch 1,2,3 you will know he " does" characters. And, if it all goes tits up, they'll get someone else.
It's no fun being an immortal Time Lord, I mean, we get one shot at life and should make 70 years in one vehicle, however, the Dr is pretty careless having had some 12 re-incarnations in the last 50 years or so.
I was never that keen on Capaldi so have no problem with JW in the role, she was excellent in Broadchurch although I'm hoping she doesn't try that Dorset accent in the new role.