Tellarites:
My favorite thing about DSC so far is what they've done with the Tellarites. Gorch (who appeared in season 1) wasn't a great example of the new look, but Tevrin Krit and the S31 admiral both made me fall in love with the new look. The vocal processing made sense for the Tellarites, and I like it. Before, the Tellarites were like pig men in space, mostly a joke. Enterprise made them worse. This new look is more like a warthog. These are guys you don't wanna make mad.
Nahn:
I liked that the creators brought in a canon Star Trek species that wouldn't be controversial to bring in. The Barzans were a one-off species that I'm glad may be expanded upon further. I also like that Nahn is being portrayed as her own character first, rather than a representation of her entire race the way Saru, Dax, and Worf were. I'm sure we'll see some of this develop during DSC's season 3, but hopefully it will simply add some flavor to her character rather than be the entire dish.
Linus: I was surprised this guy was a Saurian. I like the idea of bringing a background species forward, but I'm not entirely certain I like what they did with this.
The Kelpiens:
There were two things I wanted to happen here that haven't happened. I wanted the Ba'ul to somehow be related to Armus, since the visuals are so similar. I guess this could somehow still happen, but I'm not sure how. Secondly, I wanted the Ba'ul to be right, for the Kelpiens to turn into a major threat due to their 'evolution'. Both could theoretically still happen, but the finale doesn't give me much hope for the latter situation.
Airiam:
Thank god she wasn't an android! The explanation given for her augmentations made sense (though I wish they'd made her an alien like a Troyian or Zelonite, etc). The other explanation I'd love to see at some point in Trek is someone who has had unnecessary cybernetic augmentation and becomes addicted/dependent on it the way some people are to plastic surgery in today's society.
Control:
Frell. No. Control was somewhere between a nod and a shoehorn for a concept created for the novel Section 31: Control. IMO it was poorly executed. I was afraid they were gonna use Control as part of a Borg origin story, but the fact that Control was destroyed in the season finale was more disappointing.
The Sphere:
The idea of the sphere was an interesting one. I like the idea that the sphere data has become its own consciousness, which might lead to the intelligence seen on Discovery in Short Treks. I kinda like the idea of having the sphere related to the life form in the TNG episode Emergence, though I'm still not sure how I would make that work.
Finale:
The finale was good and bad and weird for a ton of reasons.
DOT-7: These were little R2-D2 like droids deployed on the 1701's hull to repair damage? I think? You can find an image on Memory Alpha. It's an interesting concept, but the visuals and the fact this small scene wasn't necessary was frustrating.
Fighters: I like the idea of fighters in Trek, and we haven't seen them in the TOS era yet. I like the idea. I did not like its execution. It looks more like a giant sex toy than a fighter.
Colt: Yep, believe it or not, Yeoman Colt was on the Enterprise bridge in the last two episodes. But wait, not this Colt:
https://memory-alpha.fandom.com/wiki/J.M._Colt,
that Colt:
https://memory-alpha.fandom.com/wiki/Colt_(Yeoman). Yeah. I hated this at first, but now I'm wondering if something's happened in the previous two years that transformed a previously beautiful young woman into a demon lady. It's a fascinating idea, but the lack of an explanation is frustrating.
Time Jump: A lot of you guys wanted this. I did not. I wanted to explore the TOS era a bit more. I wanted to see the impact of the Klingon War on the Federation and its exploration efforts. Now we've jumped to the future. Based on the Short Treks episode, I'm afraid we're gonna see Discovery trying to become Andromeda.
Like it Never Happened: One of the options to rectify the supposed canon inconsistencies was to make Discovery and everything related to it classified. Sadly this is what happened. I guess it could work on a long-term scale, where stories about Discovery and its spore drive become conspiracy theories that no one believes. In the short term, this might prove difficult.