I think a 20' boat would be great on the White river, but it might be a little long to also use it in lakes, large creeks, and big farm ponds.
I have to have just one boat to cover anywhere I want to go fishing. That's why a 16' boat would be more practical for me.
If I only used it on the White river, a 20' boat would seem nice.
I will rent a 20' boat one day this spring and see how it handles.