Well, once again I'm at a loss for words, because everyone else basically said everything. Here's what I can say, though. I always thought Combusken looked ridiculous at best, the overall design of it never really worked for me. I probably also never really liked that Torchic when from being a cute little chick to something very unchicken like in the next two stages, so I was probably a bit biased based against Game Freak's overall decision.
I suppose I've forgotten the whole "fan art usually makes things better rule", which is usually something I vouch for. Afterall, talented fan-appreciation of Pokemon is really why I'm here. Then again, a person'll never look up anything they aren't particularly interested in. Or can even remember exists, if that.
So having said all that, I'll admit that this is the first time I've ever seen Combusken look like anything other than silly. Again, I'll admit I haven't seen many Combusken pieces, either, so this honor falls squarely on you.
All of the above has more to do with the Pokemon itself than with your art in general. Now allow me to bring you more into the picture. The one piece that really sold it for me was...
People probably don't know me for it yet, but I'll probably become the person known as the biggest advocate of characterization. I'm sure that's a picture of you using a Combusken avatar, but even if it wasn't, I think the sheer relatability of it makes this picture alone worth it's weight in gold. You probably got a lot of laughs and "I've been there's" from this picture, and why shouldn't you? It's something I'm sure all artists have done before, especially ones who are more serious about drawing (I sort of am, I'm really more of a hobbyist who still soaks up as much as he can from industry professionals. I used to be an animator, but after a while, I didn't like it. However, I still appreciate the power of illustration and I really enjoy staying in the animation industry loop. I have too much love for it to throw it all away. If anything, it's just something to fall back on, but I don't want to make a career out of drawing anymore ^_^;).
I think art like the one I've pointed out connects to people on a more personal level, and it transcends just being another pretty picture. I've seen a lot of Pokemon art, most of it is good, some of it is REALLY good. I'll save a lot of those pics to my hard drive, as well. But the ones I remember are another thing entirely. And the pieces that stand out to me are the ones injected with personality. Some of my absolute favorite artwork doesn't have a lot of masterful coloring techniques, or the line art is really scraggly, but it just exudes so much personality that I can't help but smile, and maybe even laugh every time I see it. It's also the reason I like Pokemon comics, because (typically) it's grounds for a lot of characterization and different types of personalities. Even if it was just your slice of life story, if I can feel for the characters in the story, you've already won me over. I think that's amazing, and it's so simple, too. :)
Also, this picture sort cinched it for Combusken, too.
All in all, fantastic work, but I really really like the pictures that give the creatures more flavor.
OH! One more thing. I would say my favorite art for art's sake piece is this one.
Which I believe has nothing to do with Pokemon at all! Honestly, that's not even a shocker. :D