We used to go to Franklin, PA, but then discovered they close in the evening, so we went to Titusville, 6G1 which has self serve and is a nice quiet airport. So POU to 6G1 then a stop at my brother’s house at 4N0 in Michigan before continuing to KOSH — but around the south part of Lake Michigan and up the VFR Chicago Fly route.
From both the DC area and NC, I just head direct to GYY and then duck down and shoot up the lake shore until clear of the CHI class B and then turn direct OSH.
While CHI won't let you into the class B, visual services are available and MKE is very friendly as well.
Even IFR, i tend to cancel before CHI. They always want to send me to KELSI which is way out of the way.