Thank you for the pictures!
At first, I wasn't really in to the colour of the horse but now I find it classy with the dark bronze and dark purple under it! Love the dynamic pose of bat and horse and its paint job. I find the concept of the base great "Shogun batman trampling on jokers face/head", the two broken parts of the jokers head are great, but the center and back part of the base feels for me a bit underwhelming.
I find the rock leaning against the horse right back leg a bit awkward; in shape, size and smoothness, its like he has a black eye.
I feel that the wooden spikes can have some variety or even better a small battle damaged portion of a barricade sticking out of the ground with a banner at it back of the joker left face part (horse butt side). The weird rock can also be replaced by the broken barricade as I mentioned.
and having one or two broken weapons (prefer rifles, its more of symbolic way) and a few arrows scattered gives it a more of a feel that there is a fierce battle going. The part beneath the horse belly could have some vibrant grass and maybe a small body of water.
I hope XM Studio can tweak the base so it will have a magnificent base like the Poison Ivy one they produced recently (would pay more and wait longer for it if needed)