As I've been creating my own set of Chibi Kingdom Death minis, I've found that some of the monsters have such bizarre proportions that there's no need to convert them into chibis.
Overall, my approach is to have the minis become less distorted and cute as they get larger (the way that Final Fantsy, Pokemon and Super Dungeon Explore do things). So, a lot of the very large monsters don't need to be altered. Instead, I try to paint them in vibrant colors that really let them pop out. I also create the bases using chibi faces rather than the normal ones.
So, here is my Sunstalker: