I am generally against using light rail as a hope for building solid regional transit.
First off, at-grade light rail shares the road with traffic, so all it does is serve as a much more expensive bus that is constrained to a trackbed. The worst of both worlds. Being constricted, the trains cannot go around traffic and vice versa. This would tie up traffic and create a headache.
If one were to build a transit system, go the fully nine yards and build grade-separated rapid transit. Subways and/or El's. The trains are fast and don't have to deal with traffic. Buffalo's metro-rail line can be considered rapid transit in the underground portion.
Obviously Buffalo is not getting any new rail lines soon because:
1. The guvmn't. The Federal government has a very low priority for urban mass transit projects. America's minds are all still stuck in the cars, highways, and suburbia gutter
2. Uselessness of downtown. Rapid transit system are only effective for ferrying commuters to a centralized employment district. The Buffalo area has embraced auto-utopia, so most of the good jobs are out in the suburbs in far-flung places, not well accessed by mass transit.
3. Ease of getting around by car. This kinda ties in with #2. Buffalo is famous for the old saying "you can get anywhere around here in 15 mins." Buffalo's roads are well known for NOT being congested, thefore the relatively stress-free, quick car commute. Rapid transit for people who own cars, only becomes attractive when
A. The roads on the way to work are so congested, that taking rapid transit would actually be faster.
B. Lack of cheap, convienent parking at the workplace. This actually plays a factor in a good deal of metro rail's rush hour usage.
So ok, expanded mass transit may look bleak in Buffalo, but if the original line was built all the way to the Amherst UB campus, it would have gained more usage and made more people accoustomed to getting around this way.