a guy I know who is completely not me is in the early stages of rebuilding his basement Ye Olde Technoe Labbe and asked me for help so I am DEMANDING YOUR ADVICE ON HIS BEHALF also it's not me I swear

I don’t think the latency is too bad. It’s never bothered me or been noticeable but I don’t think I’m picky. The software has improved recently - they have a quick and easy version and a deep in the weeds version. The easy version is new and a godsend. The kitchen sink version often left me befuddled, especially with MIDI. I’ve never tried it unhooked from a computer or iPad so can’t comment.

But based on what you’re saying I think you’d be better off getting a mixer and a simple interface. Look at the interface as your tape deck and run the rig in a way that feels familiar. That way you only need the computer when you want to record - all your mixing and monitoring can be done via the mixing board

I just plug my boxes into the interface/preamp, but I'm only ever recording one at a time. My friends who have real setups have similar signal chains to what you describe, I think. One uses Ableton for the master clock, which he says is really solid.