Josh:
This depends on exactly how your programs are set up and how your sales teams are set up. In some situations, I've found that sales people start not really caring about some alerts with a certain volume of emails.
One setup that I found worked pretty well as a balance was having the alerts broken out into different emails, with different subject lines, but not TOO many separate subject lines.
This is because then the sales people can have automated filtering and folders that sort emails by subject line. A "contact us now" form fill-out is high-priority, so that gets its own special (and human, and exciting) subject line so salespeople can appreciate it. A normal "Recycled MQL has become revived" email is less exciting, gets its own consistent subject line that the salesperson can sort appropriately.
Another option would be one dynamic, tokenized email that just shows all the information. Maybe adding a velocity email scripting token in the subject line to do that same kind of sorting logic I mentioned. The drawback to this is that I skim activity logs for leads quite a bit, and I won't be able to tell exactly which email went out without clicking into it. That makes a few separate alert emails worth the time, both for the salespeople/SDRs and for myself.
Best,
Edward UnthankMarketing Operations Specialist
Yesler