I tend to agree that, as you have described it, it doesn't sound to be a major problem. But if you have an electric fan I would, as others have said, check that it operates correctly. You could also consider fitting a manual control switch, so that you can run the fan manually when you see the temperature starting to rise in slow traffic.
It might also be worth looking at the pressure cap (radiator cap) on your cooling system to see what pressure/temperature it is rated at. If it is rated at >110C then you shouldn't boil the coolant and you won't risk loosing coolant in a traffic jam. If it is rated at close to or below 110C you could consider upping it to a slightly higher temperature/pressure specification to be on the safe side.
