>>1808648In order of cost/effort:
More buses and bus stops. Cheap, almost no construction work needed, and provides a substitute for poor commuters.
Upzoning land near existing transit stops. Cheap for government, privately funded construction work, increases transit ridership and housing availability while reducing overall traffic.
Protected bike lanes and free public bike racks.
Not too expensive if the land is free, requires some public construction, allows people to make short trips by bike and mitigates the last mile problem of inadequate public transit systems.
Dedicated bus lanes. Costs more, needs construction, will be resisted by normies who only see fewer car lanes and buses zooming by while they're stuck in traffic. These give people who can afford a car reasons to ride buses, reducing overall traffic.
Expanded light rail. Allows suburbanites to use public transit and reduces highway traffic but costs a ton unless the government already has the line.
metro expansion/central hub station:
Transition built up urban areas away from car traffic, needs expensive tunneling, allows intercity rail to make sense.
intercity HSR:
Super expensive, reduces long range car trips, only makes sense if both cities have good public transit.
