Kentucky has a whole is one of the 5 SAFEST states.
Where to look depends on how much land you want. Spencer County is the 15th fastest growing county in the entire US (increasing 40% since 2000), so get more than a 5 acre lot might be a challenge.
I might recommend Henry County, which is about 25 miles NE of Downtown Louisville. It has a high median income and low poverty, and there is a lot of really pristine land there. The population growth is much slower, so it isn't going to all get developed in the next 10 years.
Henry County QuickFacts from the US Census Bureau
Spencer County QuickFacts from the US Census Bureau
Compared to Oregon, KY weather is more variable with highs around 90 in the summer, and winter highs anywhere from the 20s to 50s.