Not sure anywhere in Calgary really has the same vibe as Kitsilano - that place is unique even in Vancouver.
I live in the Beltline, just off 13th ave and 1st ST. Great location - but you need to put up with a lot of vomit on the streets in the morning. Gets rather quiet on the weekends though - still very "downtowny".
I'd recommend aiming for a place closer to 17th ave if you want something resembling a "vibe". Anywhere along 15th ave between 4th and 14th ST is pretty nice.
13th Ave will eventually become one of the better areas downtown to live, but that's a few years away since they haven't broken ground yet on the 13th Ave Greenway project:
http://www.calgary.ca/portal/server....y+Projects.htm
Kensington is an option - but I personally don't like it. Too crowded - always seems choked with traffic.