I’m currently using florisboard and like it.
My all time favorite android keyboard was the now defunct minuum. It had really good autocorrect and I got to the point where I could touch type fairly quickly with it. Also because of the way it was designed didn’t take up half the screen. Even though I really liked it I eventually stopped using it because I started to care more about my privacy and FLOSS.
https://m.youtube.com/watch?v=dZh8r-xErGE
The video doesn’t show it but you could expand the keyboard to regular size if you needed to type something specific.
Yeah there there’s been some unique Android keyboards over the years. 8pen, fleksy, to name a couple.
It’s a shame that the creators of minuum didn’t open source the code when they went out of business.