Add an option to not only set the cadence of the stream but also the frequency with which members of the stream can receive content from the stream.
This would allow users to set their streams up to cast each week (or with whatever frequency they choose) but would prohibit the members of the campaign from receiving emails every week. Instead members of the stream would only receive email from each cast for which they are "eligible."
Cadence = how often email messages in the stream are sent New Feature = how often members of the stream can receive email (like a wait step)
So, while the stream might have casts that happen weekly (every Tuesday at 2pm), if the stream is set up so that members can only receive email from the stream once every 2 weeks, then after receiving their first email, members will only receive an email every other cast.