Chapter 3 might be the biggest offender until you reach Chapter 8 and onwards, but that's only because the three final acts are quite short from a gameplay standpoint, but they do have a great abundance of regular cutscenes and flashbacks (lots of flashbacks). If you were to rush the rest of the game beginning in Chapter 8 at level 60, with decent builds and skipped all scenes, you could probably finish it in less than an hour. 

While it's a good game so far (halfway through chapter 6) I can't help but feel it's a little half-baked graphically. I don't mean the art style either, like some of the texture work is appalling by Switch standards.

Well it seems to have the same issue as X and the original where some objects have clearly been textured for distant viewing but nothing has been done to keep you from reaching those areas.  On the whole, the texture work is superior to X, but that means the slip ups stick out a lot more.  I think the area that looks the best is Leftheria though.  The fewest flaws and the most full use of the engine's upgrades.  But I think half-baked is a bit of an exaggeration.  It has rough spots, but I think on the whole the pros significantly outweigh the cons.  The basic conclusion I have is that the game can look rough but when it looks good, it can look really, really good.  

I think what's happened is the engine was upgraded during the 1.5 to 2 year period between the beginning of development and the actual finalization of the Switch's hardware.  And so optimization of the engine had to be done in parallel to the busiest part of development, which may have caused some issues.

But another problem here that is present in the first game and X and also on a side note is present in Zelda Breath of the Wild too is that the game is designed graphically around a pulled back 3rd person camera and assets are modeled and textured based on that.  However, all cutscenes are real time, not pre-rendered.  As a result, the camera is constantly zooming in, often winding up close up to assets never intended to be seen up close.  In this area, no easy solution presents itself but some kind of higher level of detail version of these assets that are somehow scripted to only trigger during cutscenes may solve the issue.  

Yeah Leftheria looks the best cos it most showcases the improvements to water reflections and grass rendering. 

And yeah, the cutscenes get way to close to a lot of textures.

But during regular gameplay, the game just doesn't have the level of fidelity I'd expect from an exclusive first party game on this tier of hardware; it really feels like one of those launch window titles like, say, Resistance Fall of Man or Perfect Dark Zero where the devs haven't quite figured out the hardware.

There is a chapter later where I think everything looks real nice. I won't say what.

Yeah, I can see that on a minor level.  I still think overall it works out on the positive side.  It reminds me more of something like The Elder Scrolls IV Oblivion.  A clear step up from what there was previously on a technical level, but still more to be done.  And I think some of this is also coming from Monolith Soft working with new techniques and the strains those new techniques bring I think took them off guard.  Grass system changes are one of them.  I think lighting is another.  The most distinct new feature is the cloud simulation which is dang impressive.  Another reason Leftheria looks so awesome since it really is a great showcase of the cloud sea.  

Hopefully this will be fixed in later Switch titles.
After first-party teams, and tools, have adapted to the console.

Yeah I will say the cloud simulation is freaking awesome. Forgot about that for a sec.

Oblivion is a good comparison point actually cos it has that same sense of having one foot in the current gen and one in the previous, so to speak. Like, some stuff like materials, reflections, and foliage got upgraded but other stuff looks like legacy Wii U code left over from X. Similar to what we saw in a lot of early PS3/360 and PS4/Xbone games where they were kinda a mix of old and new tech.

By contrast, a game like say Mario Odyssey very much feels like a full-blooded Switch game, head and shoulders above its Wii U predecessor.

Well in XC2's defense, it has to contend with more technical complications under the hood than Mario Odyssey.  It's not by coincidence that platformers, shooters, racers, etc are the launch titles to flex a system's muscles.  Fewer moving parts under the hood means more time can be devoted to the technical polish you can see.  

And yeah, Oblivion is a good comparison as well in the sense that you can clearly see the developers are coming to grips with certain techniques and capabilities previously unavailable.  I know I keep harping on it, but I think the foliage system changes were the cornerstone of a lot of the struggles.  It can't be overstated how much a leap in demand it was to go from billboard grass to grass made with multi-plane meshes.  Or going from having few if any proper trees with numerous leaf planes to shooting realistic(ish) trees with dense leaf planes.  And the shadow improvements also seem to have taken their toll.  Honestly, because of how the development worked out timeline wise, we get a cool window into all this with the trailers.  You can see how they struggled to come to grips with how to optimize some of these things by looking at the various videos.  

Also worth pointing out this is the first time they've had a launch window/launch year game, so that's probably part of it.  Usually Monolith Soft works later in the system's lifespan.  

Anyway, I do think the upgrades and new systems found in this iteration of the engine are very promising.  Once they iron out the wrinkles, they should have a hell of an open world engine.  I'm excited to see what they do with it later in the Switch's lifespan.

I meant it more in the sense that Odyssey presents a very marked graphical improvement over 3D World in almost all areas, whereas XBC2 by contrast feels like a smaller step up from Wii U to Switch, with some areas improving and others not so much.

And yeah, I suspect much of it boils down to Monolith not being as familiar with the hardware as they were when working on X, as a result of releasing early in the system's life. What's more, I got the impression the game was maybe a bit rushed in the final stages, as it was looking pretty rough at E3.

I'm also very keen to see what their second Switch effort looks like, now that they'll have time to master the hardware.