individual attention is always a great motivator for my personal practice---from the years of many many workshops I've taken, the things that stick out most in my mind are the simple corrections instructors gave me ("use THIS part of your back", "keep your knees together", "don't be afraid to use your height"...)

in general, though--even without individual attention--I think a good workshop is one that gets my blood pumping, either in the literal sense (great workout), or the figurative (inspiration!). I think with your zest, you have no worries about the latter...and having taken a few of your workshops, you don't have to worry about the former, either (o:

I think the one thing that tells me it was a good workshop for me is how much I retain and can use weeks or months later.

The workshops that I get the most out of divide the focus between a detailed breakdown and work on a particular subset of moves and then take that subset of moves and give me ways to put them together into combos for use with whatever I want. For example, a workshop that focuses on folkloric turns and footwork, or perhaps an introduction to layering while traveling. Something that ties together a subset of moves which then are used to form small combos on the fly.

Choreographies are fun, but no matter how many notes I take, I find that they fade too quickly afterwards and that the other uses a particular move or group of moves may have gets lost on me b/c the association with one particular piece of music and choreo is so strong.

OH - and another workshop I never seem to see, but I think would be great for continuing dancers would be methods of choreographing (solo, duet, group, etc.) . I know everyone does it differently, but having a session that lays out the tools and then exercises where you work to choreograph short segments with the others would be a great help to those of us who have less formal training.