We made this small Forge mod. It makes every creeper wear a nice hat and a monocle. We took some inspiration from this old Classy Creepers Mod for Minecraft 1.3.2. The mod is based on Mixins/Injection and is currently only compatible with Forge 1.8.9.
If you are interested in trying it out for yourself, you can download it here.
Credits to PascalDash for making the model.
Please let me know what you think and what we can imrpove