I think fans would be more into an XL screen for the Switch

See, I think the issue with an XL screen is the portability factor. People already complain that the Switch is too big to be as portable as a 3DS or Vita, which a mini addresses.

The Switch is already 7", so the next standard size would be 9.7" (anything in-between might not be enough of an increase), which would make it about the size of an iPad. I really don't know if there would be a market for a device that is less portable, weighs more (I'm always afraid I'm going to break my Switch if I only hold one Joy-Con because I grab the remote or something) and so forth. Not to mention a higher price, potentially a need for a better screen and other things.

even more wanted - a power boosting dock.

Well, the power boosting dock is deeply rooted in the desire to have the system updated, without having to outright buy another Switch. It would also make the pro model more affordable, since they could use larger parts, sell it separately and so forth.

As far as the desire for power, this stems from wanting to see more games on the Switch or in my experience anyway. Even if the Switch can't run, say, Destiny 2 on the go, some would like to have the option to play it on the Switch.