>>280940703
I feel like the whole body merging/control and regen are already pretty strong as is, it's just that Kishimoto didn't really draw scenes to convey that in a good way.
Also, it's funny that Kabuto was the one to reach the maximum of that kekkei genkai, which implies the brothers either didn't merg with anyone with useful abilities or simply don't know they can do that.

>>280889223