I've both camped and stayed off-field, once at the dorms in Oshkosh and multiple times at the dorms in Fond du Lac. Except for the time the kids and I drove from NC I have always rented a car, so would drive in daily and park. I don't like being tied to shuttles, and have thing about having my own wheels.
Getting there, I have more than once flown into Chicago and rented a car. Once (noted above) the kids and I drove from NC. Then last year I flew the Citabria from NC and ended up at Fond du Lac due to the soggy conditions at Osh. Each approach has its good/bad points, but flying the Citabria was the most fun.
Honestly, getting in/out isn't bad unless you are trying to leave right after the airshow. The lines move fairly quickly and they marshal people into parking places quite effectively. I've never had a problem with it. Also, once you pay for the day you can leave and return without paying again as long as you hold onto your daily parking pass. (Or, that is how it has worked for me.)
We looked at getting a hotel/motel room this year, and the prices and availability, even a few months ago, were astounding (i.e. high prices and low availability). I would actually enjoy camping (we camp every year at Sun-N-Fun) except getting enough camping gear there to make the experience tolerable can't be done flying commercial. Camping with the limited baggage space available in the Citabria wasn't viable either. Maybe when the RV is finished.

Being on-field really enhances the experience (IMHO) because you are fully immersed. But if your wife doesn't like camping .... I can't blame you for not wanting to go that route! This year we'll be down in Fond du Lac at Marian University again. Its spartan, but we frankly don't spend much time in the room anyway. So its just a place to sleep when we come back exhausted after a day of wandering the field.
As others have noted before, the first part of the week seems best. Whether at Osh or Sun-N-Fun we tend to bug out the last Saturday morning early. Crowds get worse on the weekend, and many interesting planes have often bugged out by then too.