You could run a Smart supressin list as your filter? If they click an email remove them from the supression list if they Dont ( over X amount of days) Add them to it? That way it's always dynamic and you dont have to worry about the SEND list... just the supression list.
i'm new to marketo here but that seems like it MIGHT work?
If the Email Asset ID is the same, the Lead will not get the email again. If the Emails were cloned to be separate for each Stream, then it's possible to get the same asset again if the Lead did not previously receive that Asset ID.
Sometimes I do this purposely with the expectation the Lead will remain in the Stream the whole time.