What determines nomadic clan land demand?

Just started out playing as a nomad in 9th century (the Old Gods bookmark). I immediately started conquering more land for my Khaganate and discovered that clans will often demand so much land that you must make them more powerful than yourself before they become satisfied. This effectively leaves me with two choices. Grant them that much land, decreasing the probability of revolt but strengthening the clans and thus increasing the chances of it succeeding once they revolt. Or two, don't grant them land and live with the higher probability of a revolt but keep yourself stronger and thus decrease probability of it succeeding.

However, I would rather not have this additional instability. Hence, what determines how much land the clans demand? Is this something that can be mitigated?