Hmm, I guess I have different styles, but I have noticed that three of my characters, Ashen, Ashleaf, and Avis, are based off of things I have gotten/created in real life.
Ashen was based off of my Sonic the Hedgehog OC (One of the four), called Ashen Grace. Same colors, scar, everything. Ashleaf is based off of my cat OC, also called Ashleaf. Same design, colors, everything. Avis is based off of two fox figures I have, called Avis and Ave.
I've noticed, also, that a few of my characters have something red about them. Fire, well you can tell by her looks. EmberFlower has red-orange markings. Emerl has some red on her. Naoma also has red about her design. And one of my other characters, Ferra, has red scales and such.
I also see myself designing characters with something unique about them. Whether it be markings, some items, or something else.
To sum it all up, I make characters based off of something in real life (Or some OC of mine), I give characters something red about them, and I give my characters something unique.