Species:

Like!

Human. Examples x x x
Humanoids, mythical, undead, and otherwise. Examples x x x x
Monster, aliens, mythological creatures, and non-conventional anthros. Examples x x x x
Robots! I love Robots! All the robots. No examples, only robots. 

Not my thing...

Ferals
user-made species
Fandom characters (unless asked for)
Furries or anthros solely based on regular animals (Exception: Crows, and feather dinosaurs)
"ordinary Joes" (as in a person who is not unique in any way other than just being a guy). 

 Colors:

 I have less against colors, I would rather list what I don't like

Pastel color schemes, main color being pink, orange, white, or yellow (tertiary or secondary colors are fine)
natural colors with no highlights (unless in a post-apocalyptic or desert theme)

Themes

Like! 

wasteland, post-apocalyptic, or desert. Examples: x x x
Cryptid, monsters, eldritch horrors, Lovecraftian, and anything based around death. Examples x x x
Scifi, dystopian, space, cyberpunk. Examples x x x
Neon Punk, raver, eye bleed, any kind of subclass of punk, even pastel punk. Examples x x x
Medical horrors x x (except for the first one)

Maybe??? These are designs that I have liked in the past but can be hit or miss

Carnival.
Modern.
Historical.
Fantasy.
Mythology.
Object heads. g
em/rock themed (not steven universe)

not my thing...

Food-Themed.
Decora, fairy-Kei and the like.
Anything cutesy or feminine, like princesses, wonderland, ect.

Add ons that I love
Masks!!!
Horns, wings, tails
extra limbs, eyes, mouths, ect.
plant-like parasites
scarves, especially scarves that work as arms
prosthetics, modern or cyborg esque
floating/ spectral hands and limbs
bones and/or skeletons on the outside
Black fog
twins, symbiote, DID, possession, anything that might make a character plural
Scars
bandages with purpose
chains
tiny borrower type characters. Especially when they use tiny trinkets as clothes or weapons (like a bottle cap shield, a thimble hat)
All types of gore (except those listed in Triggers)
Characters with disabilities (these force me to go out of my comfort zone to represent different people)
Nonverbal or mute characters
fallen angels
cult themes

Triggers and the like that I will not accept or, honestly, even look at.
anything relating to extreme cold, hypothermia, or frostbite
satanic imagery (pentagrams, 666, satanic crosses)
The above Plural characters where the alter is evil
Insulting depictions of mental illness
Self-harm depicted by biting
K-pop, BTS, or band/boyband themed characters
sexualized nudity or fetish characters
Christmas themes

ALL DISLIKES ARE OFF THE TABLE IS A MASKCATZ IS INVOLVED I WILL GIVE MY FIRST BORN FOR ONE

For more examples, check out my favorites folders and my Characters