I think the problem with Time and the Rani is that it never lives up to the promise of that first line. I am not sure what that promise is, but generally it is not lived up to.
This is kind of awful, I admit it, but it's also kind of fun. Quite fun is how the Doctor almost works it all out in the first ten minutes and then the Rani fucks his shit up until the end. This one seems to be remembered as another iffy regeneration, but he's actually fine when he wakes up, it's that the Rani drugs him into amnesia to get help with her plans. Still it probably does count in terms of that thing where they make the Doctor OOC for an entire story just because he's new. How are you meant to know if you like him or not? Oh well, at least he wasn't asleep the whole time like that other guy.
I suppose apart from the regeneration there's not much to make this one stand out, it's quite a Six-era-leftover in some ways. I don't know if anything can ever be as good as Kate O'Mara pretending to be Bonnie Langford, though, so I suppose there is that. This is the level of camp you can expect from this one, but idk if it is really enough to save it from being a bit shite. I don't hate it though, it's not Silver Nemesis. Probably second worst of the Seven stories, though, but there is quite a big gap between it and Silver Nemesis. I kind of hate Silver Nemesis, in case you weren't aware of that important fact.
It is largely set in a quarry and quarries are great because they look like alien planets.
Mel is quite gung-ho in this, all determined to find the Doctor and stop the Rani. That she basically just wanders about the excellent quarry not managing that is probably not her fault. This doesn't mean I like Mel, though, but credit where it's due she's not entirely feeble like Peri would have been in the same situation. We are still a year from a decent companion, but... no, I can't manage it, Mel is a bit shite really. You could always stop the story after that amazin Mel-endangering cliffhanger, skip to Remembrance, and pretend Mel died. But only if you were not a nice person, and obviously I am lovely and would never even suggest such a thing.
Bonnie is not bad at acting, it's just that her character is shite and she's doing it a bit too pantomime. She could probably have been really good if she was playing someone else entirely.
The most interesting bit is maybe that Seven hates himself when he thinks he's evil. He doesn't want to be a bad person and gets miserable about it a bit. See, I told you he wasn't mean and nasty and NAish! He's lovely! Like a cup of tea!