rating
colouring:9/10 too realistic
outlines: 6/10 you should usuially put black at some parts
design: 8/10 pretty cool but it has to have some reality to it
overall 7.8/10 good
I can't say I really agree with this.
The colouring is not realistic. Infact, it's far rather not realistic enough then too realistic.
It might have a more complex look since pokemon sprites have a very cartoony look and this hasn't achieved that effect.
Just because it's not cartoony does not mean it is realistic.
There seems to be a lightsource but the way the shadow fall and the placement of the highlights don't make too much sense.
Some real life studies should get rid of this problem.
Pokemon sprites do indeed use alot of black in the outlines (The outlines never really made much sense to me to be honest.) But before adding black is considered the lines need to be cleaned up.
Design wise it's too plain, not fancy enough for a pokemon sprite.
A pokemon usually has more to it design wise.
The large vegative area allows for alot of space to add details on.
(Don't overdo it either though.)
Basicly I really recommend you learn the basics through means less confined then pokemon sprites, since they have some specific rules attached to them constricting the learning process.
Consider not keeping yourself to the pokemon style.
Try to master the basics in general before you confine yourself.