Good ideas here.
The long pauses didn’t stand out to me during my initial installation—probably because I’m prone to flip away to another tab and lose track of time. Had I been more focused, I might have CTRL-C-ed out, thinking the process was hung.
More recently, I was rebuilding to recover from a problem, and keeping a closer eye on things. The long pauses and warnings in the logs did make me a little nervous.
If it would be tedious for devs to insert info text throughout the setup scripts, I wouldn’t mind just having an accompanying README that lists the specific warnings to expect, commands followed by long pauses, and other things to not panic about.