Communities are going to know their priorities best when it comes to what kind of transit system they need. Local governments are very good at understanding where the bus station goes, what kind of mode of transportation people need and the appropriate place for an active transportation lane to allow people to move through their community in a sustainable way that promotes healthy living as well.
The role of the federal government is not going to be to go in and start dictating where projects go; it's going to be to fund good ideas. If we actually come up with programs that communities can apply to and we can partner with provincial governments to leverage additional investments, we can grow the overall ability of people to move throughout their communities, which will help promote healthy, livable communities.
The short answer to your question is that the role of the federal government is to fund good projects. My sense is that on an individual level, as local representatives, we can work to understand what kinds of projects will work for our communities, but as a government we should fund good projects when it comes to transit.