It'd be great if Hubspot Sequences could include custom Suppression Lists and/or something akin to the "Don't send to unengaged contacts" checkbox that's available on the email marketing side of Hubspot.
Use case: A sales rep could be continually or periodically sending emails via sequences to contacts that are historically unengaged or otherwise meet criteria that would make them less than ideal to keep sending sequence emails too. Having to manually clean up the sequence contacts one by one on a frequent basis to avoid this can be time-consuming, and is very dependent on relying on every individual rep to perform a variety of sequence list-cleaning steps. Multiple sales reps that may be sharing overlapping Sequences can make this even more complex to police...
But a lot of this could be solved simply if we could create a smart list that matched the criteria we wanted to suppress against, and then apply that list as a suppression to Sequences... The list-creation part would be easy, as Hubspot already has robust tools for that; the only element missing is that there's no option in Sequences to choose a suppression list.
Providing the "Don't send to unengaged contacts" option that's available on all Hubspot marketing emails could serve a similar purpose, if made available on the Sequence level.
Or allowing Workflows to conduct more sequence-based actions could be a good solution too (e.g., "Unenroll from sequences if X criteria or action is met").
There are some workarounds available, such as utilizing workflows to opt users out of the One-to-One Email subscription-type to prevent them from getting used in sequences, but utilizing basic suppression-list options would be less complex, and involve fewer drawbacks (e.g., fully opting somone out from all one-to-one emails is a much more harsh solution then simply suppressing from sequence campaigns, and thus only viable in a narrow set of use-cases).