It... could've been better. My biggest objection is the shortened neck making the whole ship look like it's scrunching down (and right after we fixed the JJ-Prise having it's engines too close together making it look hunched-up in the shoulders. Overcorrecting!), and the TMP-style nacelle pylons. That fantail is pretty gross, too. And why did they move the black grill on the nacelles so far back from the dome? Why even have it at all?
Moreover, it doesn't really look like a Discovery ship. Every single other ship, even the relatively-unique Discovery, has been pretty standardized in terms of parts and pieces and textures, but this is entirely its own thing. The TOS pennants are great, but I don't understand why they're there, given all the other ships used the TMP pennants with the arrowhead.
I don't know, I've been trying to brace myself mentally for this by telling myself Star Trek is transitioning to a more loose production-design philosophy, using the Halo game series as a point-of-reference, where virtually everything that appears from one game to the next is redesigned, either moderately or radically, even after technical advancements stopped being a concern. They just dick around with how everything looks for the hell of it, which is a mixed bag considering I have my own favorite incarnations of various ships and props and characters, but the benefit is that every production team (generally) is producing a unified, cohesive product. The old stuff looks recognizably (usually) like it did, but also of a kind with the new stuff stylistically. This, though... it looks like they did it in a vacuum, without much thought for how it fits in with Discovery or the DSC Starfleet style. It looks like any generic "update the Enterprise" you might see on-line, especially in the way a lot of them can make it seem kind of dinky and toy-like by thickening up the proportions, making it look blobby, rather than muscular (which I'm sure was the goal), which is another issue this version has.
And, of course, they've also got the problem that the TOS design was already updated once, and it was perfect. That would've been my first step if I couldn't just gussy up the original. "Look at everything that didn't change between the series and the first movie. You can't change that either. Anything else, you can change, but not the same way as they changed it for the movie. Make sure it looks more like the series version than the movie one when you're done. Go."
I really think this cliffhanger tease was a terrible idea. It doesn't offer anything beyond the promise of fanservice (not even actual fanservice), it seems designed to imply the Discovery crew is going to be overshadowed in their own season premiere, and it hems them into a starship team-up when they clearly haven't come up with a good idea for it, yet, or else they would've ended with that. Even if they were committed internally to using the Enterprise in the next season premiere, they should've kept their powder dry and devoted the full strength of season two pre-production to redesigning the exterior, especially since they're aching for some sort of VFX reckoning with regards to style, polish, and consistency that'll probably alter the look of exteriors in the show. I wasn't expecting the Star Trek Beyond version of the Enterprise-A to appear in the next movie as-is since the next director would almost certainly have their own desires for what a new Enterprise should look like, and they've opened up exactly the same issue on DSC. I'd say there's no more than a 50/50 chance that that model appears as we saw it tonight in season two.