I'm from Iowa city originally but most of the gravel riding I have done is south of Des Moines. Lots of hills where I would never worry about stopping and would try to take my momentum through so I don't have to work as hard going up the other side. The problem with the hills here isn't necessarily that they are long, although they are. But what happens is they are steeper at the top and letting the bike roll when there are sharp corners may not be that great of an idea if you only have a rim brake and are not confident in their stopping power.