One of the ratsnakes you should definately check out is Russian ratsnakes. They may grow a little larger than 5ft, but are supposed to make very good pets. I have not seen any local to me, or I would have a pair myself.
Some other ratsnakes you may want to check out: dione's ratsnakes, twin-spotted ratsnakes, bairds ratsnakes, gulf hammock ratsnakes, japanese ratsnakes, mexican night snakes. Also consider the trans-pecos ratsnakes. They are awesome! There are probably a lot more in that size range, but are you looking for the best pet, or the brightest colors, asian or north/central american, or what in a snake?
Pakistani jeweled ratsnakes are also a very beautiful snake, which changes color until it reaches maturity, into an orange snake with usually a black head and black speckling on its body. They, however, don't usually make the best pets in the world.
A really cool, small snake, that isn't considered a ratsnake, is a lyre snake. I haven't seen any available as CB, but have seen some long-term captives that were eating mice and seemed to be doing well in petshops and collection. They stay pretty small and are just neat to watch.
African house snakes are really cool. Western hognose snakes are nice.