You shoul be able to repeat the same job on the press sheet using the repeated page order.
In terms of ganging different jobs. If you submit them as a job group you can then join them and impose them cut & stack.
ganging multiple jobs on the press sheet requires the output management license.
That will allow you to use the "job group" page order in imposition (you also have to enable the Collect Job Documents option in the workflow itself). That will also allow you to use the asymmetric imposition which gangs up jobs of different dimensions into the same press sheet.
The output management license also includes the collect node which will automatically create job groups for imposition.
You can have Collect wait until you have N jobs or wait until it has been holding jobs for a certain amount of time.
The job group imposition also has behavior in which it will not impose jobs if there are not enough jobs to fill a sheet. The workflow can then route jobs to another imposition which can be configured to fill the sheet with fewer jobs.
