Kate, some technical info also:

Low profile rims produce a less harsh ride - Mavic Open Pro is probably the best known for this.

Offcenter (OC) rims offer more strength because it allows more equal tensioning of the spokes from side to side. Velocity Aerohead OC are well known for this combined with a low profile.

Hubs - a difference in flange height from drive side to non-drive side helps with spoke tensioning. That's why White Industries hubs get such great reviews and wheelbuilders love them.

Spokes - it not just the number. The number of cross, the butting, the weight of the spoke, etc., come into play. Radial spoking of a front wheel can produce a very harsh ride.

Hope this helps.