For the keyboard I would try Florisboard on f-droid, it gives a lot more spacing and sizing options. I basically make the keys as wide as possible and then play with key height. The bottom offset let’s you raise or lower the keyboard as a whole to suit your grip.

I was a long time AnySoftkeyBoard user until a year or two ago when I finally decided Floris was just better. I’ve tried FUTO keyboard a little bit, it seemed fine but didn’t offer enough customization options.

Calyx has you relock the bootloader similar to graphene so it shouldn’t flag as rooted.