Deregulate bus routes. Let the private bus operators choose their own routes and switch between routes at will (as long as they complete a full run on a route before switching to another — you wouldn’t want to get on a 135 and have it become a 120 five minutes later).
Each route has its own peak hours and peak directions. If you allow bus operators to change routes, free market dynamics will go to work and the most active routes will get the most service. And the bus operators will come up with the most optimal route, i.e. the routes that will transport the most passengers with the least expenditure of fuel. For the passenger, that translates to better travel.