While that first question was extremely important for him to raise the strength of the people around him, and under him, the second question was related to the possibility and probability of his plans.
Furthermore, he didn't like the fact that there was another uncontrolled variable in this little planet, that might endanger his future plans and control of this planet.
He had to make sure that nothing like that happened, and that there were no difficult opponents left, otherwise he would never be comfortable leaving his kids and his wives in this place.
Even though he would love for them to follow him there, since his three wives were already pregnant with his children, he couldn't do it.
It would not only be dangerous for them but even for the unborn babies as well. So, he was thinking of going there first and creating a foothold in the Immortal World before taking them there.