FreeBus
Seattle subsidizes the bus ride each person takes, with most of the cost coming out of taxes...to get more people to use the bus system, it needs to be free altogether.

The difference in additional cost in taxes will be made up by SC, then covered completely, as resources allow.

First the inclusion of more regular busses, another 1000-2000 for peak time travel to lighten the load, and increase passenger satisfaction.
Later all these busses can be gifted to some other area in washington state, wherever they may best serve those most needy.

Later buses specifically modified for the FREEBUS system.

Additional investment in technology including OVERWATCH, and fingerprint security would help to manage the quality of the system, and vastly improve each ride, which is an issue at the heart of why greater numbers of people dont ride.

The fingerprint system would be system that temporarily captures the fingerprints of passengers who depress one of many units on a bus...in order for the bus to move....forcing everyone to take responsibility during their trip...if anything occurs that needs to be investigated the record is there.
With standard checks by the driver/supervisor after every trip for vandalism, and littering, etc.,
which when correlated with records of those who have abused the system kept off the busses altogether...no more guesswork.

Infrared/ultraviolet/visual sensors would mark each person depressing the fingerprint units until only those who haven't are marked, making it easy for the the bus driver to direct his/her attention to those people.

Distributed microphones would establish everyones voiceprint, and add it in records as another way of differentiating between people that need to be identified in cases of misbehaviour, also knowing that conversions are being recorded would be another way for people to keep their personal issues off the bus both between each other and from any phone conversations...

Further.  Why the hell does Metro not have an explanation for lateness of busses or their absence altogether when the technology is there to INSTANTLY report on each busses progress and current situation.

This information will be logged and sent to all bus stops from mobile transponders, which would have digital readouts that would offer a real time map and tracking of the primary bus(es) for the stop and the reverse side offering inquiries that would answer all other questions input in any language or verbally interrogated.
No more guesswork about your bus......all schedules....traffic and emergency reroutes, etc., instantly.

Also a text and automated phone messaging system would handle sending out messages to those who subscribe to a change of service notification system.

No more slacking bus drivers either. What watches the passengers, watches the drivers.

More nighttime buses especially to all the new attractions that are to be emphasized....such as the library, the night parks, etc..
Many of these would use neon lighting and play soothing musical compilations at low levels.