Views from the southeast are best for Halifax. There are lots of good views from Dartmouth, Eastern Passage, the islands, or if you're on ships. When you are actually walking around the city normally you don't see much of it at once because of the hills.
Here is one view from George's Island, by
Antonkolbo on Flickr (can't find any panoramas unfortunately):
View from Eastern Passage, by
Nancy Rose on Flickr:
The best vantage point that is easy to get to is the Woodside ferry terminal (taken by me a couple of years ago, scroll ---->):
For Vancouver my favourite skyline views are along various beaches west of the downtown: