Actually, all the patterns look very good!
You asked which pattern looked the best, and I've got to agree that a variety is probably best. I suspect that if I were doing it, I'd think of some reason to use the least time consuming method for a disproportionate share of the surface. I like the really small cobblestones on the left for use in alleys of the "let's go get mugged" variety. The larger cobblestones (top center) start out not so good, and get better as you go along. The best ones could be done in different colors of stone for the ruins of somebody's really ornate courtyard.
The flagstones on the right bother me, and I'm not sure why--perhaps because the spaces between flagstones is uniform width. I think the square pieces at the bottom are wonderful, and the stones on the left are beautiful and method of making them is just scathingly brilliant!
You mentioned wanting to try rectangular cobbles. I've seen rectangular brass tubing at stores that sell radio controlled aircraft things. I think these are in 8 or 12 inch lengths, so they could be cut into several smaller pieces then take a hammer or pliers to them to create slightly less than perfect rectangular cobbles.
Grelber
