Time And The Rani is probably the worst ever Who story IMO (just edging out even Fear Her and The Twin Dilemma), and, yeah, that initial clip is the lowest point of the show's darkest hour - just utterly abysmal, woeful even (although I can't bring myself to hate on Kate O'Mara - terrible as the serial is, and as nonsensical as it may be in plot terms, I kinda love her Bonnie Langford impression later on in the story).
I have to disagree with the hating on the pulse scene, though. The build up to it - especially when Seven falls fictim to some Mel-Fu - is dreadful, no doubt, but the bit where they actually check each other is brilliant - the only beacon of light in an otherwise awful set of episodes (though I could have done without Mel's random "Ah, yeah, I know all about regeneration for some reason, let's just skip over the explanations and get on with the adventure, eh Doc?").
In terms of Seven's tenure as a whole... I don't hate it.
I don't rate it as highly as some do, but I don't hate it. Sylv's on-screen depiction is probably the lowest-ranked for me (though he f***ing nails it with Big Finish), but too much of the televised stories are utter gash IMO. Rememberance, Fenric and Survival are cracking stories (and you can't shake the feeling that in Survival Ainley is finally getting to play the scary Master he always wanted to, and clearly relishing every second), Battlefield and TGSITG aren't bad, and I have a weird, dirty and utterly secret love for Delta And The Bannermen, but the rest is outright poor IMO. It was improving, no denying it, and Season 27 would probably have been legitimately great assuming the rate of improval continued, but as it stands it's nothing special IMO.
I think that the nail was hit on the head when people mention that season 26 looks so good in comparison to 24 and 25.
I also think that retrospectively our view of Seven's era has been changed. People always talk about McCoy's dark and amnipulative performances as the Chessmaster, and as Time's Champion etc., but watch the episodes, with no thought to what came after, and... there really isn't much there of that persona at all. Sure, he's a bit manipulative of Ace in Fenric, but otherwise the dark Doctor pulling the strings from behind the scenes is only really present on screen in a few scenes in Rememberance, and in the premise of Ghost Light.
The character that we think of as Seven is almost wholly invented by the Vigin NAs, and carried forward to Big Finish - we've then all retrospectively applied it to his TV stories. Sure, he was definitely getting darker as the seasons went on, and I do feel that the NAs were a logical continuation of what was on-screen, but in terms of his three seasons on air, McCoy is nothing like the Seven that fandom recognises or perceives.
Not saying that's a bad thing (or a good thing, come to that), I just find it interesting is all.