Hmm, that's not a bad metric. Maybe I can write up a special function for the metro lines that computes headways in the Market Street Subway and incorporates those into the status calculations.

The main issue is that until I go through and rewrite the whole thing to do long-polling for every line, it's expensive to compute each route since I have to make several requests to ProximoBus to get all the necessary data. Caching for five minutes helps, but it's still less than ideal.