Lovely design, I like it a lot.
I like the way you use a ramp to switch hot ends.
Only addition I would add is two screws to adjust the height of the nozzle. I know you use the orange bits and the angle with the clamp screws to adjust the height, but I found that adjustments like this are usually better done with actual screw thread. So besides the clamp screw I would use a perpendicular screw to adjust the height.
I really like the idea of magnets, it is a good way to get a positive "click" and the fact that there can be no oozing, lovely.
Lykle
