Just make the existing buses easier to use! Chicago has implemented a bus tracker that does for many bus routes what a BRT upgrade does for just one. The biggest complaint about bus service is timeliness, and this system addresses at least part of that problem by providing a real-time status.
Too expensive for our regional plan? How about SMS updates when a bus will arrive (text stop and route number to a short code and receive an automated response) or an IVR that provides the scheduled bus arrivals for each stop. Portland uses the latter approach by assigning a short code on each stop; dial one central number, enter the code, and the system tells you the next arrival time.
You don’t have to buy new buses or expensive LED displays to provide what centralized technologies can do for a much lower cost.