Congrats. I don' t know the terrain around Columbus but you are correct that we have a mixture of transplanted Rios, Merriams, Easterns and Hybrids. The turkey population here is growing well so you should have a great time. Most of the turkeys hold along the river ways. I personally hunt some river bottom forest along the Missouri.
Become a forum member at the below NGPC site and post a similar message in the Nebraska Hunting section and I' m sure some locals will give you some additional info.
http://www.ngpc.state.ne.us