Well, I'm no expert, but here's what I'd look for....
1) Know how to play the position. By this I mean...understand how to cut down angles and know where to position yourself to give you the best opportunity to stop the puck.
2) You have to be agile, cause that bad boy comes in at 100 MPH and you can face a barrage of shots at times, and you have to be able to move.
3) Hand eye is extremely important. Again, that puck is coming in fast and it's not very big...so you have to be able to see it into your glove.
4) You have to be a little nuts. You cannot be tentative or scared of the puck. Have to be agressive and fearless and willing to sacrifice your body for the game.
As far as being a general out on the ice...I don't consider that too necessary...however, you do have to speak up if you're being screened by your own guy or something like that.
I think, though, you can be an outstanding keeper without being an on-ice leader.
That's just a quick thought on the subject.
Jim