Rclone mount - limit upload speed and simultaneus uploads?

I'm not sure what your question is as a copy command and a mount aren't the same in how they operate.

A copy, you can limit the # of transfers and checkers and such.

A mount you don't have transfers are you have people/processes accessing a mount.

You have:

 --bwlimit-file BwTimetable             Bandwidth limit per file in kBytes/s, or use suffix b|k|M|G or a full timetable.

which I use to limit bandwidth per file.