For my latest game idea I needed custom characters, and I remembered a thread on the forums a while back that offered just that. The thread was a major b#%$& to find, but here it is in all its glory: Layout Starter Kit. Yes, it’s meant to be for testing only, but it also serves as a great starting point for a character of your own. Because the package is not cooked you can right-click on the mesh in the Content Browser and export the original 3D assets, then import them into a program like Blender and start molding them to your liking.
Even better, the creator says:
"Do what ever you want with it, I don't even expect credit."
Of course, giving credit where credit is due is always good practice. So thank you Chris Newman! For those of you who find the link broken, use this one instead or you can email me for the files.