Right, let's do this. I won't quote Keane's posts, but I'll have headings so it's clear to which part I'm discussing.
Zelda and Mario
In Nintendo's defense, the new Zelda was being developed for the Wii U originally, as such, all the praise it gets for trying to expand and refine is justified, but doesn't necessarily indicate that Ninty's just now changed their development. Mario, I'm agreed with. I think the fact that they're trying to shed that casual gaming demeanour and try to focus more on core gaming again might have helped them in shifting to newer and fresher ideas. If memory serves, some of their games on the Wii U tended to be fairly pedestrian but marketable to a casual audience. Why Zelda managed to be immune to all this, I don't know, but I'd imagine it might be because Zelda didn't really have the same family friendly appeal. Then there were games like Star Fox Zero, which, from what I've seen, was decent, but hindered by Ninty's insistence on the Wii U's gimmicks.
Console and Hardware
Some have likened the Switch to the 3DS at launch, brimming with potential, but lacking the right start. I know some have criticised Ninty for bringing motion controls again, and loading the JoyCons with so much hardware to the point where they're very expensive. It's a fair point, and I can't really argue with it. However, personally, I feel that Nintendo's implementation allows for the best of both worlds, and could allow for unique experiences for those wanting to provide it, while also not losing traditional experiences due to having a radically different control scheme. The local Wi-Fi is pretty neat indeed, and shows the portable aspect of the Switch off nicely. Them getting rid of Region Locking was a long time coming.
I know folks are apprehensive about the Switch not being as powerful as the PS4, but I feel that it might not have to be. I think so long as it's powerful enough, it should suffice. We know that it's powerful enough to run Unreal Engine 4 games, so I'd hope that porting games shouldn't be too much of an issue.
There is the matter of storage. I understand why it's not as large as the 500GB-1TB that the PS4 and Xbox One has, since those are HDDs, and the Switch's portability limits it to flash storage. Given how digital stores are pretty much a must these days, and the size of modern games, 32GB is rather insufficient. Though there is SD card expansion, but I've read that it's not a fast standard, so that could affect games being played digitally.
As for the price, I'll admit, if it were £250 it'd be somewhat more tempting, but given what they include, it's understandable.
Games
I think we've discussed quite a bit now about how Ninty, despite talking up having a lot of games, isn't really giving the best impressions with what they've shown. Barring Zelda, there doesn't appear to be much appeal in the launch lineup, and many third party titles in the launch window are just ports. Having some of these ports launch all the way in the latter half of the year is rather underwhelming. It feels like many Third Partis are just trying to test the waters after the Wii U, which worries me a little, since if they're not convinced, the Switch could very well sink as the Wii U did.
Then there's 1 2 Switch, which I've said before, feels more like the Wii Sports for the Switch, and I feel it's a real missed opportunity not bundling it with the Switch. On its own, at full price, it's not lucrative, it's a party game at the end of the day. Having it bundled allows for it to show off what the Switch can do, without having to risk any further investment. ARMs looks nice, and could be a lot of fun, but again, it doesn't feel like a core game.
Online
I can't add anything to what you've said. And I do like what that diagram you've shown proposes. Though perhaps Ninty should sort out the Virtual Console in general before trying to be funny with online subscriptions.