I totally see what you mean. Since Hugo’s said that Pots will be an extension of Targets & you can see that Targets have been designed on the backend to be based on things other than categories, I’m optimistic that the functionality will get more flexible when the current accounts launch.
But whether it’s Targets or Pots that you end up using, I expect you’ll be able to achieve what you want to soon 
PS I’ve just spotted this topic & your ideas follow on nicely from the discussion that’s been had here so I’ve moved our posts over. I hope that’s ok.