That's right about Aaron C in 1830, the ages of the household members don't match the 1820 and 1840 man/men. But who is he then? and where did he go?
The 1820 and 1840 Aarons might be the same man, the ages roughly match. 1820 he was "engaged in agriculture" acc to a far right column on the census.
The 1830 man should be findable at familysearch, by the way.
I didn't look for "Cunningham Perry County history" so give it a try. Or with Meade County.
------
The only pictures I saw on ancestry were also on familysearch. I only remember one, I think of Lavinia Hines (Johnson) Wilks/Wilkes, who might be your Mary Esther (Johnson) Cunningham's sister.
---------
Regarding Ester (Babcock) Barmore. I misled you. I don't know how or if she is related. Focus on her husband Dennis. All the Barmores I found on the Ohio River came from the Finger Lakes region of upper NY State. Chances are your Esther (Barmore) Johnson did also.
Both in 1850 and 1860, as head of the house--so presumably the source of the information--she said she was born in NY, not Indiana, as the trees say. I would believe Ester's word over the trees. Her family might have moved to Indiana soon after she was born. The Barmores in the area are probably all connected somehow.
There's a slight chance Aaron C came from the same area, but nothing points that way as of now.
-----
A couple questions you might look into for leads:
1) Esther (Barmore) Johnson was evidently widowed in 1850, living in New Albany, IN. She had $500 in cash but no land or occupation. Even her son wasn't working. Who was supporting her? Was there a relative in the area?
2) If your Franklin Aaron C married Mrs Dunn in 1849 in Meade Co KY, then Mary E Johnson in Jeffersonville IN in 1860, how did he know Mary E Johnson was there? Was he from Jeffersonville, or was it because he was already a merchant and had contacts? or what?
----
Look on familysearch for all the resources for the states involved. They might have images of some early wills or deeds that aren't indexed, so they wouldn't show up in a search.
----
And I enjoy working on the older families. They are a challenge to do, since there are no vital records and the census info is minimal. You have to look in different ways. Hopefully you will find someone who has done the work and published it and got it right.