Not too many routes that don't really take a long way around. All offer different things to see/do. Going up Howe Sound via Squamish, Whistler and Pemberton takes you through the Coast Mountain range. Get into the Fraser Canyon at Lilloett & Cache Creek and on to Kamloops. This would be my favored route as I like the coastal range.

The other two routes would be out through the Fraser Valley to Hope (not too scenic), then either up the Fraser Canyon at Hope to Cache Creek or direct via the Coquihalla. There's more to see and do past Hope. Pretty scenic if you're from the lowland east coast but somewhat ho-hum to those of us who live here.

See: http://www.th.gov.bc.ca/Circle_Route...outes_home.htm