Gamepad / Steamdeck experience bonanza (megathread)

I played a few hours of 0.50 on my steam deck and came away with the following annoyances. Some of these are known issues; I'm centralizing them to show just how many rough corners you run into back-to-back. Several of them are dealbreakers or render some sections of the game's design space inaccessible unless a non-controller thing is used. I'll keep updating this post with additional issues as I run into them.

• Performance in game mode is really bad unless the SteamDeck environment variable is set to 0. Probably has something to do with SDL's steam deck virtual keyboard support. The performance problem goes away if menus (e.g. inventory, pause) are open. This is also only in game mode, not in desktop mode. #7498
• It's weird that the controller menu system is off by default. I sorta get the tooltip bar being disabled by default, but the menu system being entirely disabled by default seems weird. To be clear I was not even able to get into the game from the main menu without using mouse emulation.
• Certain menu windows have overly large minimum sizes and do not fit on the screen if a large (e.g. 1.5x) UI scaling factor is used. As a heuristic, nothing should ever have a minimum size greater than ~600x400 (slightly less than 640x480).
• Controller UI: the mouse cursor for the left-analog-stick-driven emulated mouse does not visually appear. The effective mouse position still changes and can be used, but I can only see what I'm doing via looking for mouseover highlights. The hardware mouse cursor stays behind even though the effective mouse position changes. If I use Steam Deck mouse emulation then the effective mouse position goes back to the original position where the hardware mouse cursor was.
• I really need to be able to set mouse and stick camera sensitivity separately.
• When equipping items from the inventory using the controller UI, the equip sound gets doubled: #8797 (closed)
• Controller UI: the tooltip bar looks awkward when it intersects other UI elements, and also I think the background is slightly too opaque. Making it slightly more transparent and making the top edge fade out instead of being a hard edge would be improvements. This is a nitpick but it's the kind of thing that's probably really easy to improve. It looks better when I turn the general menu background opacity down, but at default settings it sometimes almost fully blocks things that I might want to be looking at, but only partially, so the thing peeks out from under it.
• "Auto run" walks by default, and there's no way to make a controller binding for "always run" so that I can control whether "auto run" runs instead of walking. The keyboard controls list has an "always run" control, but the controller controls list does not. I had to bind a controller button to a keyboard key in steam, which isn't a solution.
• Spellmaker spells need to be named before you can buy them, but you have no keyboard, and there's no way to get an automatic name. I had to bring up a virtual keyboard, which isn't a solution. I also cannot make manual save files for the same reason; I'm stuck using only quick/auto saves.
• Controller UI is buggy in general: resizing some windows causes them to shrink etc.
• Directional menu-item-focus control inputs need to "echo" so that you don't need to repeatedly input them to navigate long lists or grids.