As you can see from my OP, I'm mostly banking on Japanese third party support, with minimal support from Western studios (though I do hope their position changes if the Switch becomes a success).

I see a lot of people dismiss Dark Souls very easily.

I'm not saying I think Dark Souls is likely going to happen, on the contrary I have little faith for it. But I believe it would make much more sense than many other potential ports. From what I can tell from personal experience the series is very popular among long-time Nintendo fans, plus it's popular in japan where there's a stronger demand for handheld gaming.

Lastly, and most importantly, due to wireless local connection capabilities they could add local multiplayer - both in co-op and PvP forms - something that people actually can't get on PC/home console versions.

I'll comment about some of them:

There is a good chance that Monster Hunter XX will be launched as multiplat for both systems, yes

Yooka Laylee has a good chance of coming to the Switch, but maybe not as a launch title

Dragon Quest IX has been annouced to be coming to the Switch a while ago, but probably not as a launch title, especially for the West

Persona is more for PlayStation, so I don't see it being ported

Just Dance, Yooka-Laylee, Monster Hunter and Dragon Quest XI are a given, I´d say.I wouldn´t get my hopes up for Souls games...as for Persona 5, maybe but not alongside the PS4 version, a few months after.

I reckon From Software is up there for a reason and Dark Souls 3 makes the most sense... I mean, even the Wii U got some Assasins Creed games and what not. It even got a remaster of the original Darksiders as late as 2016. Why would Dark Souls 3 for the Switch be so strange then?

I don't think it's going to be huge at launch but most games after launch for the first year at least could launch on it. If they sell decently then more games will release for the NS.

That will be interesting. The way I see it. Switch has the right ingredients so far to absolutely blitz the Japanese market. However I can see the PS4's Western dominance being an acchiles heel to it managing to grab exclusivity of even many Japanese titles that the publishers feel could/would do well in the West.

I'd therefore see the Switch getting multi plat releases a plenty, but the lack of exclusives would hamper Nintendo's efforts to get better Western marketshare.

Obviously Nintendo are more than capable of striking deals/marketing/pricing the system in a way where it is more than capable of securing a decent chunk of Western interest though. It'll certainly be interesting to see how it all pans out.

Vita was my dream handheld. Switch actually looks like it can beat it in every way for the reasons I loved the Vita. I just hope it's software lineup is not held back by the same lack of Western 3rd party support.

Well I got 6/11, not bad. Dragon Quest Warriors 1 + 2 over Dragon Quest Builders, but my line of thinking was correct at least. :p

A shame we didn't see the South Park game though.