Chris,
As far as finding the other pieces of the puzzle, I think that will be less of an issue if you create AO profiles that can be used for multiple watchers rather than using a 1:1 relationship. It will still be an issue, and I think the only way to address it is good documentation. I personally prefer to use a wiki.
Yes, you would need separate AO profiles for anything you want treated differently. To simplify a bit, you might be able to encode the count into the subsystem ID. So if you were using 3.1 as your base subsystem ID, then 3.1.X could mean to wait for X events before making the alarm visible. You still have to create at least one AO profile for each value of X you wish to support, but that makes it easier for anyone to remember the meanings of the subsystem IDs. I suppose another possibility would be to create a single AO profile that calls a Lua script, and the script could look at the subsystem ID to get X and use that as the counter.
If creating separate AO profiles, you might also want to limit the options for the values of X. For example, it might not make a lot of sense to support both 3 and 4 because they are so close, but 10 and 20 are very different and probably worth supporting separately. It just depends on how flexible those making the rules can be.
-Keith