I think it would be a combination of parameters that includes everything like reputation, account age, posts, organic votes, etc. We all know the regular stuff.
But I think that there is this one crucial element that we don't have a parameter with which to measure it. I think it is how much you are valued by the other users on Steemit. In fact all the other parameters like reputation, SP, etc. are just the indicators of that.
Although it might not be a visible number but sometimes it is better that way. I think there are times when you can tell when a user sends this mental signal of appreciation that you are somehow able to catch. I think that is the 'black belt' moment.