Personally I like the original the best out of the three designs.
I don't know what you're trying to do with these guys in comparison to Pokemon, so I'm just going to give you advice as if you were just making straight-up, official-type fakemon.
First off - Try using more saturated and brighter colors. Pokemon tend to not be dull. Here are three I picked out that I think you could take colors from:
Secondly - On Pokemon, when an organic shape such as fur or grass is being represented, it is simplified like woah. Take a look at
Wooper's "antenna" vs a real
Axolotl's. As you can see, Wooper's antenna aren't as feathery, but they have the same color and position so they get the point across. I think this problem is most visible in your evolved form's mane. Try simplifying it, looking at Arcanine and Ninetales for examples.
Third - shading. B/W style sprites usually have no highlights and very simple shadows. I would recommend, once you fix your colors, cutting down to two shades per color - unless what you're shading is supposed to be very shiny/reflective. Then a highlight or two is okay. In addition, dithering was only used in Gens 1, 2, and 3.
Finally - Your design, although a bit complex, seems like it'll look fine once you fix the sprite itself. However, Pokemon usually have large, expressive eyes. I use official Pokemon as reference for most of my eyes, and there's a handy chart
Here.
Your work reminds me a lot of
my work from 3 years ago and I think I've come pretty far since then.
Good luck, and keep spriting!