Hey man! I used to do an acoustic Solo project and would do live loops. It's such a fun & creative way to get a full sound live when you're solo and it's also a complete party trick to those in the audience
So win win!
My setup was a boss RC30 with a boss AB footswitch (to switch channels with my feet while I sang), going into a Digitech whammy pedal (I used this to emulate thick bass tones and give a sort of baritone guitar vibe to my tunes) I would also have a designated 'looping mic' going straight into the RC30 to layer harmonies too.
The RC30 has two channels but I know the RC300 has more if you're planning more complex stuff
My advice would be to start simple and to experiment as much as possible to figure out what the loopers limitations are with your tunes (for example with the RC30 I was unable to go to a completely different section in a tune - a modulation for instance - because I had already locked my backing vocals in the home key) I'm sure there are ways to figure out anything you want to do if you're crafty enough with what you're using though. That was just my experience with the RC30. I've also been waist deep in a loop and messed up - LIVE!
I had to stop to stunned silence and restart the whole thing - that's just a horror story though.
In terms of people killing it with a looper - look no further than this alien from outer space, Mike Love
What you see at the start is impressive - but watch the video until the part where he stops and starts live looping the acapella vocal middle 8 (4:23) - Genuinelly one of the strangest and most impressive things I've ever seen someone do with a looper
I remember trying to replicate it and gaining a whole new respect for the guy - you'll see what I mean!
Hope this helps