Two Jack Lake is another beautiful lake in Banff NP and you have to stop by if you're heading to Lake Minnewanka as it's conveniently on the way.
It's a gorgeous spot for a picnic or photography and one of the best Banff's spots for a paddle. If that's what you're planning - make sure to check out the canal that runs from Two Jack Lake along the campground as it often has very calm water and no wind (in oppose to the lake that often gets windy).