I like the idea of adding a filter to auto-link ticket IDs, and may do just that (thanks!), but that doesn't seem to solve the issue of aggregating results for tickets of the same type.
To clarify, I want to be able to have a single assignment that "contains" an arbitrary number of individually-graded tickets from which it derives its grade. It looks like this way a student could keep a regularly-updated list of ticket IDs, but the assignment would still only support a single grade. Am I missing something?