you should know where the buttons are already

but I do regularly imagine what a simpler keyboard would look like

something with less than 20 keys even, since you could totally do things in software to make typing easy
I feel like you could easily use an IME with a 12 key keyboard and do damn near everything you'd ever want.

5 keys for each hand for general input, and then a key where tab is and a key where enter is
wouldn't really guess anything, you'd be able to get specific keypresses consistently, even if you had to press more than one key to do one keypress