I just realized how insane Megumi's domain will be once it reaches completion, especially in a domain tug-of-war against other DE users.
The added boost he receives from Chimera Shadow Garden is by far beyond any other domain boost we have seen in the series - he virtually multiplies his strength by a factor of 1.2x, AND can create multiple clones of himself and his Shikigami to take advantage of the boost, AND allows himself to devise a strategy using numbers in this scenario.
I'm not even taking a tamed Mahoraga into account.
In a domain battle, a Megumi at his peak should reign supreme. Sukuna might be the only odd one out.