Thats exactly what Saddam did and it was the following elections that netted him the 100%. Fancy that. 
I wasn’t really aiming for a discussion of the relative awfulness of the world’s despots.
You’re making assumptions here. Qusay may be even more ruthless, but he alone can only do so much harm. Without the establishment WANTING him to succeed his father, he won’t be able to take over. You’re assuming that all those Ba’ath people loyal to Saddam will also be loyal to Qusay. You’re assuming none of them thinks he himself should be rewarded for his loyalty to Saddam by succeeding him and has some support for that claim. Qusay may be just as ruthless, or even more, but that does not mean he has as much support.