I used to have a Rikenon fisheye in the 90's (I believe it was a re-badged Pentax) which broke, and I have missed it since.
Last year I got the DA10-17 fisheye, and I love it. I had some boring but important use for it in my profession, but I soon found many more interesting ways to use it. For a while perhaps too much (the kids were asking after last x-mas why the x-mas-three was tilting in the pictures, but really it is an excellent tool when trying to fit all relatives, the x-mas tree and dining table in one picture). It's good for street shooting and people, good with some sort of "macro". Purple fringing is there in some situations, but I can't say it have disturbed me. It must be impossible to make such a lens and make it fulfill normal criteria for what is quality in a lens, so I tend to forgive it for its weakness thanks to its other good sides. I have not felt the max aperture as a limitation, as it works so well now with the K20D to turn up the ISO. You are not going to play around with razor thin DOFs anyway on such a lens.
Though I am looking for some extreme wide angle or fish eye with an aperture ring for my LX I haven't owned a fish eye prime at the same time as the DA10-17 and hence not been able to compare them so I can't really help you with your actual questions. But I can say this that I suspect that it is the best you can get for a digital camera with a 1.5 crop factor. If you buy a fish-eye made for a film SLR you don't really get a fish eye, but a bad wide angle on your DSLR.
"Macro" with the DA10-17. Is this what I would see if I was a bee and came in flying right after my sister-bee?