I also use ble.sh and I'm happy about it. Didn't want to install altshells because sometimes stuff I install includes instructions on what to add to bashrc to make it work, and other times programs might rely on bashrc being used and even put something there automatically, which is ofc a terrible practice, but it happens. Not ever having to translate commands/config from bash to another shell is a big win for me. I mostly use just a simple history-based autocomplete in ble.sh.