Going one step up from BART a street car (tram) would be a good addition back into Saskatoon. I think the dynamics and perception of the service changes as soon as it is on rails. There are cards that are narrow enough to operate on city streets mixed with cars (e.g. Flexity Outlook cars).
Source: Wikipedia (Vancouver Temporary Olympic Line) See
https://en.wikipedia.org/wiki/Flexity_Outlook