AGAINST: I'm going to be painfully direct here. You are not as good as some of the commissioned artists out there who can't get work. You art style and color are good and I want to encourage you, but I don't feel like you have locked into your final art style. Looking at your work is like the early work for webcomics- it feels stiff and a little awkward like you are still drawing parts of pictures instead of an entire picture. Not that you can't get paid work, but just realize you have strong competition.
This is probably The.biggest.obstacle.
that I've felt about myself. I'm pretty sure just by taking a look at my gallery that I don't have a definite style that I stick with, and in a way that works for and against me.
As someone who is basically trying to improve himself, I find it hard to stick to one definite style because there is so many skills I could learn trying many different things. But if someone were to take a look at what I can do, they'll either think "wow he can do a lot," or "wow he doesn't know what he's doing." Honestly, I would like to try out commissioned work, but I feel that my fear of failure keeps me from trying. I guess I just have to deal with it some way or another
Some artists are blind to their flaws and never improve. You don't sound like you have that problem, so you definitely will get better. You just need to practice. What better way to practice than to get paid by people!
If you want to feel a little better, try looking at sluggy.com and questionablecontent.net. Read the last week of comics and THEN check out the first month of comics. REALLY big differences. Even Penny-Arcade. Their old stuff is so rough, so crude... almost bad. My point is that we never get to see the early stuff of most manga artists, so we don't know how they evolved and found their own style (usually), but in webcomics, they keep their evidence online. You can see where they were and what it took to get to their current style. Love it or hate it, they now have a strong style in which every stroke feels like it is in place and complimentary.
I think it is good that you try so many things. Hell, even Picaso tried a bunch of different stuff before he found his own artistic voice. How would you "fail"? Would it be a drawing so bad someone asks for their money back? Honestly, I don't see that happening unless your portfolio online doesn't really represent your skill. If someone thinks you don't know what you are doing, they won't commission work. Is someone likes your stuff, they will check out your prices and most likely be happy if it looks as good as what you have already done.
The only tricky parts may be pricing and managing expectations. That's marketing, my specialty. I recommend starting on the really cheap side until you get 1-2 commissions under your belt. Then you can start playing around with the price. When pricing, make sure you don't just do a flat price ($20 per pencil, $80 per full-color) because there could be huge differences in detail work. Maybe put something like "as low as $XX, but can go higher depending upon the size of the illustration, detail work and delivery time."
... Sorry, going into full-on marketing mode here and you don't need that. Let's stick to the basics.
1) You have some talent. Yeah, you can improve, but you also probably can get a few jobs now.
2) You know you can improve, so don't charge a fortune and look like an idiot.
3) Failure risk is minimal. No one will die if you do a bad drawing, no one will get sick or hurt and you can't take down the US finance industry or a car company with your drawings. You don't even have to charge someone if you feel like you did a bad job. Hell, if you did that, you'd probably get a great reputation and get more work anyway.
I say start. Just have no illusions about being successful overnight. Good luck!!!