Left unchecked, this guy can go hog wild, but really, can't the same be said about dozens of creatures? And even if he does go on a reanimating spree, it heavily depends on not only your own 'yard, but also on what other players have there to determine how much it can actually do.
I can see crazy and obnoxious things happening, I saw something pretty sick myself once with a sac outlet, blinking engine and a
Kokusho, the evening star in an opponents yard. But that's not often seen, very situation-dependent, and usually easily disrupted. So no, not even close to being ban worthy.
Now SP, THAT was a primordial that we can do without. Before the banning, we had a house rule that SP couldn't be copied or recursed, that didn't work because he would get blinked all the time. Then we tried to 'fix' it by house errata-ing it to say that the player who lost a permanent could search for a basic, like
Path to exile, but that made him not worth playing. In the end, we settled on changing 'for each opponent' to 'target opponent', and then he could still be problematic. I think it's one of only three cards we ever had house rules about, not counting silver bordered cards we allowed.