I know I'm a bit late to the party here, but I have some thoughts.
1. While there is a relatively even distribution in threat power level for reanimator, ranging from Colossal Dreadmaw and Spirit of the Night on the low power end all the way up to Atraxa, Grand Unifier and Griselbrand on the high power end, the actual reanimation spells do not. It's almost like The Grand Canyon. On one side, you have Reanimate, Animate Dead, Exhume, and other one and two mana reanimation effects. On the other side, you have cards like Unburial Rites, Zombify, and Incarnation Technique which are pretty good but not nearly as efficient. But, the center between those two power levels and the "river" in the middle of the canyon essentially consists of Necromancy and nothing else, at least for unrestricted reanimation effects.
2. Because the power distribution of reanimation effects is not even, balancing reanimation falls more on the end of choosing the correct targets for the environment. Sure, you have to pick between the high-power or one of the various lower-power clusters of reanimation effects for your Cube, but you can make up the difference by selecting more appropriate targets. For example, you might find that the broken reanimation spells with bad targets is still a little too good for your Cube, or restricts your top-end creature pool so much that you can't do what you're looking for. In that case, it might be better to play worse reanimation effects and better targets, just not the literal best cards. Instead of reaching for the S-teir targets like Atraxa, Grand Unifier and Griselbrand, you may opt for B-tier or C-tier options like Woodfall Primus or Waker of Waves.
3. If you end up having to pick "lower power" reanimation, you also have the option of picking effects that are capable of being used in non-combo decks or are capable of reanimating multiple times. Unburial Rites is a good midrange card if your deck is full of big beaters with reasonably powerful ETB effects, such as Siege Rhino and Thragtusk. Meanwhile, Incarnation Technique and Whip of Erebos are capable of giving a player the opportunity to reanimate multiple creatures with only one card. This rewards decks that are able to efficiently stock the graveyard with good targets without forcing them to go all in on one spell.
I've opted for the approach of using A and B-tier reanimation targets (Stuff like Archon of Cruelty, Apex Altisaur, and Dragonlord Atarka, but no Griselbrand or Atraxa, Grand Unifier), and weaker but flexible reanimation. I try to keep my reanimation fairly open-ended, so while there are a couple reanimator specific cards like Incarnation Technique and Whip of Erebos, the other cards such as The Cruelty of Gix, No One Left Behind, and Unburial Rites all have homes in other decks (or are just generically good). I like this approach because it lets me keep a reanimator deck in my format without having it feel like a glass cannon– it's basically a midrange deck with a powerful but beatable combo finish.
more. Some of the others in the cycle too. Especially the scrying and surveiling ones.
