I agree this would be a useful enhancement. Presently, the only way to achieve what @d_bray is discussing without creating multiple tasks is to use a scheduling mechanism such as cron and calls to the QEM API to achieve successive execution of the same replication in an interval smaller than 24 hours.
I support this idea. My use case however would be to schedule a task every other week. Having a repeat frequency on all schedules would be extremely helpful.