[skyking]

removing the front wheel is probably the easiest aeromod available.
My beetle and mountain bike combo I took to commute every day for a year, but not at freeway speeds ever.
I could see bike wheel in either mirror. If you took off the front wheel, and used a disc brake block if necessary, you could shift it sideways to get the bike into the wake more properly.
I made my own hitch mount bike rack to get it as close to the back of the beetle as possible. That's the other thing, tucking it in tight to the rear of the car.