Mainly because it's Straight tail, individual seats slide back (better leg room for back seaters, earlier than c model are bench with horrid leg room and no baggage area to speak of), CG works compared to newer straight tails, and if we re not getting the limo setup the 225hp c33 and earlier are just not worth the lateral move.
I sat in one of them last summer, the ergonomics are improved for the back seater, mainly because those seats slide aft. I took a tape measure to the cabin and it is 43.5 inches at the elbows in the front, which is basically Mooney F/j elbow room. Not enough to lateral over my arrow (41.5) if that was the only criteria as you note. So essentially, I sold the wife on 160knots and bat out of hell climb rates of the 285hp. But, they're hens teeth and the newer ones run out of CG for my mission believe or not. Not that it matters, I'm not spending f33a money on it.
Outside of that exception, my earlier criteria still stands; we re still looking for the limo at arrow speeds or better. The search continues, and I'm not opposed to getting creative, especially with airplanes people love to hate, if it gets me the right discount.