We have land in SE MN. There are certainly ways to make money with the land you would purchase, but I can't see any way that the income would exceed the expense of purchasing and owning the property. If you do purchase, I would recommend renting the tillable out to a farmer. You should be able to make more than you would by having it in CRP. Additionally, and probably more importantly, the farmer would be helping take care of those tillable acres. In CRP, you'd have to find a way to meet the requirements of the contract which could mean a lot of upkeep. We have ours in CRP but it is very tempting to switch to renting it out in the future for more income and less maintenance on our end.
Timber could certainly help produce an income, but I imagine it wouldn't be a regular income...more of something that you could potentially use to offset the cost of purchasing the property. We haven't done this on ours yet. Supposedly it can be good for creating cover for the deer as well.
We rent out the house on our property too. It has been a good deal for us. We don't charge them much, but they help us in lots of ways, so it's worth it. We haven't had any real issues with our renters wandering the property.
Since we don't live on the land, our income does little more than cover the property taxes.
Being that you're from CO, I personally wouldn't make the purchase unless you were planning on moving here or are able to spend a fair amount of time here working on the property and enjoying it.
That said, you can have some of the best whitetail hunting in the world if you find the right piece of property in MN.
If you do decide to move ahead with purchasing a property, be sure you look at who owns the property around the piece you're looking at. Our property is bordered by other folks with large chunks of land. This is much preferable to being surrounded by people that own 5-40 acre parcels and everybody on those parcels wants to shoot a buck or two.
You might want to check out some of the videos Bill Winke has on youtube with High Point Land Company. They have been putting some videos out recently on purchasing a property, and his experience is in the general area.