I don't think you can influence this in a way that you have 10 x 10 kB/s uploads.
The only thing I know about is that slider that lets you toggle the upload slot limits.
The higher you set that value the less uploads with higher speeds you will get. The lower you set it the more uploads with lower speeds you get.
According to my experience the upload of people are never the same. It seems to depend on many things. Maybe the credits, high/low id and such stuff.
But if you want higher upload values with fewer users at the same time, keep the slider at the highest value (right side).
I hope I could help, at least a little bit.