Hey Dave 
if you are looking for standard AJAX behavior with a UJS like interface while still being able to use Turbo / Turbo Streams, I could point you in the direction of Mrujs. (A library I created intended to be a drop-in replacement for rails-ujs)
If you have any questions, feel free to stop by the StimulusReflex discord and I’d be happy to help in anyway I can.