First time I saw this is thought it would make and easy conversion into a Demoneater model. With the addition of a bull centaur at the back of it and turn the catapult bit around, add a hammer, mace, morning star or fist and walla?
I think the scale would be fine. Mantic stuff is working well for me. It seems some of the detail might be a strange choice… seem there is some arm or person behind the front plate/shield.