BTT is almost perfect - well done for producing a great product!
One feature I really miss from my Karabiner days is being able to remap keys based on the number and position of fingers on the trackpad. My fingers would then rarely leave the home row, with either left/right/both thumbs down allowing everything from VIM style editing, app switching, etc.
This was - by far - the fastest way of working, as multiple control keys, key sequences, trackpad gestures and the Touch Bar all require moving away from the home row, so interrupt any typing flow.
thanks again,
Daniel