Doubt he'll actually see this here, but I don't have a Twitter account, so:
The way battles currently present things is way too slow. A bunch of things really should probably be combined and/or incorporated into animations instead of being text. Max raids severely exacerbate this issue by having 4 Pokémon on one side of the battlefield.
Also everything about how online matchmaking works is just really bad in Sword and Shield. They really need to go back to a more PSS style system where you can just select someone from a list and request to battle or trade with them. The codes would be fine as a supplemental system, but they're terrible as a primary one. Also, if raids, or something roughly analogous, are a thing they intend to actually keep, then they also need to give that it's own dedicated matchmaking screen that updates in real time. I still don't know how to get the Y-Comm to reliably add new cards, and so many of the ones it does show are either full or not actually seeking participants anymore.
Having a GTS in Home is nice, but not being able to also access it directly from the mainline games adds a whole bunch of annoying extra steps to using it. It also kinda reduces the utility of the GTS since trade evolutions don't seem to work in Home.
Speaking of Home, having two apps with such vastly different capabilities is just a pain. I can't even get the phone app to display my Pokémon as they are laid out in the boxes.
Having to manually reconnect to the Internet every time I return to the game from the Home menu is annoying, especially since this has been a problem since X and Y.
There's a bunch of situations where a "send to a box, but let me pick which one" option would be nice. Especially for raids, because selecting a Pokémon could mess up your active box.
Also if the Pokémon are going to be on the overworld, then they should actually reflect whether or not they're shiny. Going from non-shiny on the overworld to shiny in battle is just weird.
