Yes - buses.
I actually think the lowest hanging fruit and one of the better value projects for Calgary Transit isn't the LRT downtown, but it's figuring out how to get those hundreds of buses moving on 6th, 5th and 4th Avenues downtown.
Enormous delays and inconsistency have been allowed to fester for decades undermining much of the citywide bus network's usability thanks to how important downtown is to many routes, but none have priority so are victims to heavy congestion every day.
A redesign of major downtown avenues with proper bus priority is probably the best value short-term transit project downtown.