Is there any demand for an expansion of the Calgary and Edmonton city councils? They are rather small - Edmonton has 12 councillors plus the mayor, yet similarly sized Birmingham here has 101? Do the city councils have a lesser jurisdiction?
Small city councils are the norm in western North America; whereas Montreal has 65 members in its city council and Toronto formerly had 44, Winnipeg has 15 and Vancouver has 11. Similarly, in the United States, there are 9 city council members in Seattle, 11 each in San Francisco and San Jose, and 15 in Los Angeles.
As Njall mentioned, smaller city councils are perceived as less expensive than larger ones; it's hard to imagine that voters would decide that this perceived expense is worth whatever benefits come from having a councillor who represents fewer constituents. For the same reason that reducing the size of the legislature is an obvious populist campaign tactic everywhere, the Ontario government cut the size of the Toronto city council by nearly half a few years ago.
