Back in the 80's I wanted the best 35mm projector available. The Leitz projector was the best and had the sharpest glass and you could view a slide as long as you wanted and the projector wouldn't burn the slide up.
Unfortunately, I couldn't afford the Leitz so I bought a Kodak and put a Schneider lens on it. I had really close to the quality of the Leitz lens at a fraction of the cost. Of course I still had a cheap projector that would burn up the slides if I kept them in too long.
Normo,
For optical properties alone, probably the Leitz should be your choice.
There were two tray systems used over time, earlier used the Euro style straight tray and later the Kodak Carousel type. Either of them work well but the Kodak holds more frames(80 or 140) than Euro(36?).
From what I have read the hasselblad pcp 80 works with 35mm, but then leitz has a number of pradovit models that also work with 35mm. Since I don't know anyone personally that ever used anything but a kodak carousel, I trying to learn from groups like this and the web. One of these days opportunity will knock. Norm