What was the point of making Kaguya transform into a Juurabbit if she was going to turn back to normal within a single chapter, and be defeated in that same chapter?
Shit's happening soon after this chapter. It's just getting started. Remember, the sun and moon marks where given to them to SEAL MADARA not KAGUYA. Let's not forget about the Edokages.
the Rabbit is unstable it would have probably been easier to seal. look at it this way. why would you carry a big gun if you can have a small one that does the same amount of damage.