Yes, you want the pattern maker -- the blinds -- as close as possible and the source as far as possible to be as sharp as possible. But it also depends on how sharp the source is -- a PAR often doesn't make great shadow patterns but if it is far enough away, the shadows patterns would be fairly sharp. A fresnel makes better patterns in full flood position, and pulling the fresnel lens out of a fresnel produces even better patterns, but at a loss of output. It's much easier when you're talking about recreating a low-level sharp source like moonlight compared to a bright source like the sun.
Talking about tungsten units... I often remove the fresnel out of a 2K or 1K for moonlight effects using shadow patterns, or even a 5K if I have to gel it blue and need a stronger light. For sunlight patterns I'll usually take the fresnel out of a 10K. I've even removed the lens from a 20K when I have a big window and can back up the light, but at some point, you get diminishing returns as you move up from 5K to 10K to 20K because the bulb itself is bigger and bigger, and thus less sharp unless you back it off, which causes the intensity to drop off. But one advantage of going farther away with the light is that the rays are more parallel so there is less spread.
There is a small K5600 HMI light called a BlackJack which creates a fairly sharp pattern when you remove the lens. There is also the 7K Shadowmaker Xenon light.
You can also put shadow pattern gobos into projector lamps like Source-4's, though you get a slight chromatic fringe to the edges of shadows.
Exposure and amount of fill just depends on the effect you want to create, the mood, and how much of the face is lit by the pattern versus how much is in the shadows. If the pattern is from sunlight coming through the blinds, generally you want it to be a bit overexposed.
