I disagree with Vancouver not having character; there are lots of things to see and do! You could use it as a starting or ending point to venture further into BC. Like others have said, a slow road trip from Van to Calgary is a good idea, with stops in Whistler, Okanagan area, south-east BC (Kootenay area) before going through the Rockies to Banff, Canmore and Calgary.
I live in north-west BC, with friends and relatives in Okanagan and Vancouver Island (Victoria), so I am familiar with those areas.
I love Whistler in the summer time, there are lots of biking trails and little lakes to swim and kayak in. The Okanagan area amazed me the first time I saw it, since I didn't realize Canada had such a desert area; it's beautiful. If you are going inland to central BC, I would recommend early summer, rather than August, since we have had so many forest fires, it may block the views of the mountains.
As a proud Canadian, we have so many beautiful areas to show off. I am originally from Niagara area, with it's fruit and wine growing area, and small quaint towns once you venture off the highways. Picton was mentioned above, and yes, that area is really lovely as well.
Tough decisions on where to go; you just have to narrow it down and try not to see too much at one time.