Personally, i'm a really big fan of elemental-esque creatures. They have the freedom to mold their shape into many diff forms although I like blob-esque things a fair amount!

Wolf Hawk Lion or T-rex

How awesome would it be to have a big T-rex at your side.
A hawk would be cool so you have another Bird option a bird that would look more though than the current one. The current one looks more cute/ funny.
Wolfs are always popular in many games why not have one here?
Lion the King of the jungle! A king among beasts. And all you could do with a males mane! That would look awesome.

And if you want to be original Kangaroe.
It could be a fun idea that when you have a girl Kangaroe and it has breeded that you can see the baby in her pouch until its sold or grown to old to be in there....

Just ideas. Sorry if some where already mentioned. Didn't have time to read all pages.

I like the idea of a sea snake/serpent. You could have mutations such as feathers ( a la Mayan god Quetzacoatl), a bracelet around the tail, or fins. If not a snake, a plesiosaur would also be really cool!




I really like the idea of a head frill/ear fins like this


For lizards, a basilisk/Jesus lizard could be cool



And I would also vote for spider


or a barn owl


To get the stocky build of the wolf but have if be different from the volnixi, I would suggest either a wolverine


or a honey badger


Or something based on a springhare


or pangolin


As an extra gene for some sort of mammal, a super fluffy squirrel tail may be nice.

Something like a slime?

omg yes, pangolin. Cutest mammal ever.

I agree with the suggestions for raccoons, red pandas, and badgers.
Or maybe something like the hocyxa?


I also like the dinosaur idea. Maybe an aquatic one like the plesiosaur?

Thought I'd post some more specific non-mammal suggestions to back up my previous post...


Seahorse

I think a seahorse would be rad. Preferably not too much emphasis on the horseness, since we already have a deer and a horse. Carousel mutation would still be appropriate though. Another mutation could be appendages that make it look like the leafy seadragon.

Snake

There's just a lot that can be done with this critter. A short and stubby one could be really cute, and a subtle reference to tsuchinoko (the mythical creature which Dunsparce from Pokémon was based on). Wings/feathers can be added à la Quetzalcoatl or fins à la Loch Ness monster. A rattle at the end, a bell at the "neck" or a cobra-style hood. And there are all kinds of beautiful patterns snakes can have naturally in nature. This can go in all kinds of directions!

Spider

There has obviously been a lot of support for this in the userbase. I think a cool idea might be to make "Pygmy Vorkids", a smaller tamed/domestic version of the enemy monster. I would especially love a cute, big-eyed/small-bodied one like jumping spiders. The hourglass from the black widow spider could be one of the genes. Though not technically a spider, Daddy long legs are cool too; perhaps a mutation could provide the extra-long legs?


Also throwing my support to some particular species which a lot of people don't think of as "lifelike" I suppose, but which I think can be really charming!

The Tasmanian Tiger, or Thylacine.

Extinct, but VERY unique. I think a lot could be done with them in terms of genes/mutations too. Obviously, all the pictures of them are black and white as they died before we had the color stuff, but there are drawings of what their colors were like.




Their HUGE mouths:



and for color reference, stuffed ones(not that colors mean much since we can change them, but it helps some. hehe):

I'd love to see the following as pets:



Gryphons
Quetzecoatl
Phoenix
Wolves
Ferrets
Lemurs
Chinese Dragon
House Cat
Wyvern
Red Panda
Sugar Glider
Falcon/Hawk/Eagle
Owl
Zebra
Dolphins
Spider monkeys
Squirrels
Cereberus
Bats
Coyotes
Caracals

I'd love to see a squirrel pet as well ^_^