I agree about the Sixth Doctor and Peri having a warmer relationship works better (it's interesting that this seems to be more due to how Baker and Bryant's acting choices rather than anything in the script) (the Doctor apparently betraying Peri in Mindwarp wouldn't really work without this warmer relationship, it doesn't really work anyway but for other reasons).
I think there's an issue with most of the 1980s companions (until you get to Ace, anyway) that it's never really clear exactly why they are travelling about with the Doctor. Nicola Bryant plays the part like someone who is convincingly terrified and having a horrible time going to all these awful places where her life is frequently put in danger and she might die an incomprehensible ditance away from her home, which is interesting sometimes, but the tone is inconsistant and there's no real sense of Peri doesn't just ask the Doctor to take her back to earth in the 1980s, she'd make more sense as a character in the original 60s set up where the Doctor can't control the tardis and is trying to get someone back to their home planet/time. This is probably an obvious point, but I think part of the reason Colin Baker works better in some of the audios is that when he's paired with Evelyn Smythe he seems like less of a bully, someone who will give as good as she gets wrt rudeness and stubbornness.
― soref, Monday, 20 June 2022 21:55 (one year ago) link