Since almost all of the shows I was following have already finished airing, here are my final impressions (not including the shows I have dropped):
Gakeppuchi Hotel: my absolute favorite of the season. Lighthearted and genuinely funny in a warm, respectful way. Good vibes 100%.
Seigi no Se: another unexpected favorite. A little bit too cliche for my liking, but still very fun. I especially loved Ken Yasuda as Aihara. Also: Takemura family shenanigans and the (so very timely) tokusatsu hero episode.
Black Pean: biggest disappointment. This show had a lot of potential (neat intrigue; story that brings up a bunch of extremely relevant up-to-date problems plaguing academic medicine and the world of academia in general; good cast; probably a decent budget, too) and the first episode did seem promising, but then they pretty much ruined it with lazy writing. Episodes 8&9 (most recent) were particularly awful; at this point the only reasons I'm still sticking with this show is to see if they give Tokai a better ending, and because I really do like the cast - many of whom still manage to do a good job whenever given a chance despite the poor script and execution (all those bizarre close-up shots... quite a few TBS Sunday shows are guilty of this peculiar, somewhat cringeworthy filming style, and it isn't not entertaining in its own way, but I feel like Black Pean has finally crossed the line).
Mikaiketsu no Onna: okay-ish but I probably wouldn't have watched it if both main characters weren't ladies. Still, if they make a sequel or a special focusing on Narumi, I’m in.
Miss Sherlock: neither the criminal cases nor the Moriarty storyline were particularly engaging or impressive, but I LOVED Yuko Takeuchi's Sherlock and her interactions with Wato -especially in the first half of the show- and Reimon and Shibata in the last couple of episodes.
Monte Cristo Haku - a rather mediocre take on the classic revenge story; wouldn't recommend. Personally, I watched it mainly for Hirofumi Arai, who was amazing as Kagura (by no means likable, but boy was he convincing in that role).
Ossan's Love - another favorite, this time as expected. Cute story, very fun, and hopefully a step in the right direction for Japanese television. I did have a few problems with the writing but would still recommend 100%.
Signal - neat? I wasn't particularly invested in this one but I enjoyed it quite a lot nonetheless. Good acting, too, although most emotional scenes (crying etc) were too stretched out.
Confidence Man JP - not bad but perfectly forgettable. It did manage to surprise me a couple of times, though.