I am of the opinion that the Switch is already on the cusp of being too big. I've gotten very used to its size and accepted it as a compromise between being big enough to have a display of adequate size for tabletop mode (and, of course, house and cool its internals) and being small enough to still be within arm's reach of actual handheld size.
So I guess in summary I would say that it's already a smidge bigger than I would like, and I don't think I'll be able to adjust to it being even bigger and heavier.
It's been five years now, and longer since the TX1. Surely they ought to be able to put something more powerful in the same box. I know that Moore's law has slowed down a lot, but come on. I wasn't even looking for miracles, personally, just something a little bit more powerful in the same form factor that uses the same controllers.