Another Chiswick/Hammersmith route, via Streatham, Tooting and Wandsworth Commons and the Thames Path.
This will be nice when CW9 is finally done later this year. In the mean time there's the A4 cycle path (ugly, smelly, and noisy, but gets the job done I suppose).
Not sure whether it's better to stay south of the river at Wandsworth (follow the Thames Path up to Hammersmith) or go north and follow NCN4 around the Hurlingham Club. Probably much of a muchness - Putney Bridge junction isn't great, but nor is the rat-run around the Hurlingham.