Your best choice for a MF shooter with an eye level prism would be either a Mamiya Super or TL with motor drive grip & prism or the Bronica ETR series. I use the Mamiya with motor grip & prism and find it quite satisfactory for eye level shooting. I have a 500c but fitting it out with a prism would make it even more clumsy than it already is. With the Mamiya you can handle the shutter speed dial and aperture without moving your eye from the prism (the same can probably be said for the Bronica but I have no experience with that camera). For eye level shooting you might want to play around with one of the Fuji or Bronica rangefinders. The Bronica would have interchangeable lenses, although they are a bit harder to come by.