^ Welcome to the club, Julien ^^
I couldn't help but notice that you put 'orchestral performance music' under 'art you enjoy doing', and I just want to say- That's interesting. Really, really interesting :P
But, back on the subject, I should start critiquing your work, am I right? xD
First off, I never would've guessed that you didn't do your digital drawings and pixels seriously o_0 Are you kidding me? They look great, if I do say so myself.
I am, after all, horrible with drawing digitally. For me, when I'm drawing something, it's either on paper or bust, so unfortunately I can't really provide any techniques for improvement or helpful tips regarding drawing with a computer :/
But I really love your pixels; the way you color and shade them makes them look interesting and very pleasing to look at as well.
Second off, your style of drawing chibi is really cute ^^ The cuteness factor is a value that must be considered when drawing chibis, IMO, so that's a good thing.
Your chibi drawings also give the impression that you're very experienced with the specific style, as I really don't see any problems with your proportions, chibi-wise xD
And I love how you drew Julien (who is yourself . . . ?)
Reminds me of a Axis Powers: Hetalia character, actually xD
So, overall, judging from the drawings/pixels you've put in your post, it looks like you know what you're doing as well as make me wonder what your art would look like if you really did take them seriously.
Keep up the good work, because I'd love to see more