Switch 2 includes a number of new features and upgrades over the original Switch, from mouse controls to support for 4K, HDR, and 120fps, to the addition of Gamecube games on NSO; which of these are you most pleased about, and why?

GSync. 

I am happy they went with a sufficiently nice LCD + VRR/GSync as opposed to an OLED without it. 

This gives developers a lot of leeway that they wouldn't otherwise have in that a 45-60fps variable title is going to feel and look a lot better than it otherwise would have.

Many games that would have been locked to 30fps probably won't be now. 

120 fps. What it's really missing are pointer controls like with the wii. The switch gyro isn't the same thing and mouse controls are a worse version of pointer.

4K and 1080p for me. I have a big TV now and games thst don't bring at least 1080p look really bad on it

I'm happy with mouse controls, but I wonder if any games will really make good of it

Don't really care for 120 FPS, it's useless except for few shooters which I don't play anyway. 60 FPS is all I need

I don't have any plans to subscribe for the high tier of Switch online, so no Game Cube games for me either

Mouse controls for me. The Wii's IR pointer got me back into consoles and now the prospect of more strategy and RTS games with that kind of direct control is cool. EDIT: Plus, I could finally play more console FPS games properly since mouse controls are just way better for those.

I also appreciate the decision to use JIT compilation for the NS1 software. That way, those DRS games that struggled with low frame rates should finally achieve their top intended performance. As a consequence the titles won't be 100% compatible out of the gate compared to their past hardware-compatibility approaches.

Probably that it'll allow developers to offer 40fps modes. So more titles will be able to offer frame rates above 30fps even if they can't reach 60.

Hopefully the Switch 2 will support usb mice like the other consoles for those interested in that as you'll surely get a more comfortable experience with an actual mouse.

People will need the actual buttons that a mouse won't have.

Something like Drive X Drive wouldn't work with a usb mouse obviously, but otherwise it will depend game by game, they could offer mouse+kb support for some games like PS+Xbox do.

I'll have to try the joycon 2 mouse controls myself to see what it's like but reports from people online aren't all that positive on how comfortable it is to use. Personally I'll be playing mostly handheld and doubt I'll ever be a situation where I want to use mouse anyway, but I am curious just to see how it is.

I prefer using gamepad even on PC anyway, unless it's an RTS lol.

40fps is also interesting, and the high refresh rate screen that comes with the base model makes this feature possible. Also, HDR and VRR might become more common on the Switch 2.

Same goes with the joycons mouse mode, it's nice to have this feature built-in the system so developers can use it. Optional add-on accessories don't usually catch on.

I hope to see shells/attachments on Amazon to the joycons made to enhance the experience. I think I read something on a Nintendo site somewhere.