Doctors: Smith > Capaldi > Tennant > Eccleston
Companions: Clara > Amy & Rory (at their best together) > Bill > Maaaarfaaaaaaahhh > Donna (although the Doctor-Donna was great) > Rose (pretty much can't stand Rose) > Nardole
I didn't find Nardole as bad as some did, and I don't dislike him as much as Rose, however he was basically written in as an afterthought because Matt Lucas wanted to stay on in the role for a bit, and it shows in the writing. He's more or less pointless
.
Masters: There have really only been two in the new era, and tbh, they both just fit the Doctors they're with. Missy only works well with Capaldi and would have been awful opposite Tennant. Likewise, Saxon is like a "dark reflection" of the Tennant Doc, and doesn't work anything like as well opposite Capaldi.