This is just a proposal, I was talking about in T3419.
All jobs are still added to JobMan, this didn't change.
When queueMode is false, copy dialog has "F2 Queue" button which starts a job immediately if no jobs are running. Otherwise the job is queued for later execution when all other running jobs are finished.
When queueMode is true, copy dialog has "F2 In Parallel" button which starts the job immediately.
Start Paused checkbox is unchanged.