Nikita (S4): This was the half season they were given to wrap things up, and I think they did a pretty good job. It does show the difficulty of mixing mind-twisty spy tropes with satisfying character resolution -- which is sort of to say it didn't achieve the awesome finale of the original Nikita TV show (in its own half-season-to-wrap-things-up). But it was all clever enough (full of competing spy agencies going 'well, they did this because they want us to think that') and cool enough (Maggie Q!) and even respectful enough (Alex is a tricky character, but I think they did her well) to make it all worth the trip.
Doctor Who (various): We recently bought the 50th anniversary boxed set and decided to go through it in chronological order. This would presumably be quicker if we didn't go from Day of the Doctor to Rose. The modern show remains a bit too fast and hand-wavey for me (not to mention the farting aliens), but Christopher Eccleston really is excellent, and I'd forgotten how good Billie Piper was, before it all went a bit strange.
True Detective (S1): Truthfully I was never quite sure what the mass appeal of this was. Certainly it had moments of hellacious beauty, and Rustin Cohle was a cool guy, but the plot was a bit of a mess, and the characters in general under-cooked. Just one of those things.
The Tunnel (S1): Stannis Baratheon and Fleur Delacour fight crime! We hadn't seen either of the preceding versions of this, and just started watching it randomly on iView (I wanted to confirm it had nothing to do with the Aussie movie of the same name). It was very good, but I do think that as the 'truth terrorist' plot wound tighter and tighter towards the personal, it lost a lot of the scope and ambition that marked the early episodes.
Young Dracula (half of S4): those halcyon days of early seasons are long gone, wherein Van Helsing's main method of fighting vampires was dressing in drag (just noticed he was in Edge of Tomorrow!). Now it's all political negotiations and murder and traumatic love. It's an odd fit but so far it retains enough charm to work -- and enough of an audience that the S5 dvds are already on their way. Chloe should turn up again and sort them all out (or not).
Elementary (S1): For most of this season I was saying it was all cool, but didn't feel like Sherlock Holmes at all. By the end that had dissipated somewhat, although I suspect that is more because I had just gotten used to it, rather than Moriarty, Irene Adler etc. So yes, whatever it is, is worth watching. They made Watson's eclipsing of Holmes in certain matters believable enough to carry that off as well. (Lucy Liu is of course cool.)
Legend of the Seeker (S2): this seems mostly a joke these days (and probably always was), the Xena producers doing a more 'serious' fantasy, before Game of Thrones showed people how far the envelope could be pushed. The first episode of season 2 was indeed the most generic thing ever -- prophecies, object quests, undead beasties, lesbian warrior nuns with their dildos of pain (huzzah) -- but after that they do manage to take the various types of magic and mix them up in interesting ways. It eventually meanders a bit too much, but the characters make it worth the trip. (Though if someone had explained the concept of blind-folds to Richard and Kahlan, they would have saved a lot of trouble.)
The Dresden Files (most of): As I said recently I watched the first Constantine ep, and found it a little wanting in comparison to this, even though I believe a lot of book fans dislike it, and it never found its own niche. It's all a bit mystical-case-of-the-week, with powers-as-needed, and vast-magical-society-we-can't-really-aff
Fringe (S4): What a weird season. Everyone is an alternate version of themselves, even those who were already parallel versions. I thought they were pushing it too far, into irrelevance, but there was still lots of good stuff and then... well, it's weird. So they manage to skate that line pretty well, and it all falls apart a bit at the end. The ideas are there and are mostly consistent, but they are dealt with too fast and too perfunctorily for proper impact. Meanwhile, S5 looks even weirder, but we shall see.
Doctor Who (S8): Did I mention too fast and hand-wavey? My barriers are up, so I think this is all good enough, without being too excited or shocked by it all (as an old school fan who met Nick Courtney at a convention, I'm not quite seeing the outrage other people are reporting). Also, compared to the nonsense of Fringe, even the science isn't that bad (yeah, still pretty bad but oh well). Capaldi is good without being definitive, and I like the ideas around Clara and Danny, even if the execution is a bit woolly. Also, some genuinely creepy bits help as well.
La Femme Nikita (bits of S1): so good! After finishing the new show I went back and watched some of the original, and discovered my liking of it had not been misplaced. It's fascinating to see just how quickly things fall into place (even though the producers say they didn't know what they had, especially with Micheal), and also how good at spycraft Nikita is, right from the start. Makes latter events somewhat more plausible. I even found some more potential in-jokes between the two series (Ari Tasarov's back story! Maybe). Alas, I am destined to confuse the names Section One and Division forever. If I start getting versions of The Shop mixed up, I'll be in real trouble.
Next up: Orphan Black? Twin Peaks? Hannibal? Spartacus? We shall see.