In general, the rims on some of the newer designs with fewer spokes will be beefier than some traditional rims in order to handle the higher loads. From a physics standpoint, you want to avoid excess weight at the perimiter as it increases the wheels' moment of inertia. For my money, you can't go wrong with
www.sunringle.com. Their wheels are traditional in design and even with their rather heavy hubs are competetive weight-wise. No one at our shop has had problems with them. Easy servicability is a big bonus with them as well. Should you have issues with a Mavic hub you will need to send it back to them as they are not designed to be user (or shop) servicable, and the tool they provide is largely ineffective for making any adjustments. If you want a flashy looking set of wheels, check out Shimano's offerings. They are also a bit more compliant than the Ksyriums. Just IMHO, of course.