AGAIN LET ME BUMP IT UP A NOTCH FOR YOU ALL.
here's a good overal theory tutorial:
http://www.itchstudios.com/psg/art_tut.htmhere's a good website for premade color schemes:
http://www.colourlovers.com/here's a nice picture that is an easy reference for anatomy measurements:
http://img40.imageshack.us/img40/8190/1246817842502.jpghere's a nice website to do speed (try for 10 seconds first, then 30, then five minutes) gesture drawings:
http://www.posemaniacs.com/when you do gesture drawings, do them on real media. a sharpie and a sketchpad or something. you won't get a real feel for it if you're using a tablet. try to get the absolute basics of the figures, their center line and then generalize their limbs.
here are some tablet gesture drawings I did, because I can't find my scanner for the life of me. they suck because of the tablet, but you get the point (speaking of which, you should buy some art pens and start doing your lines on real paper, it'll look more natural).
as for more direct pointers, qc's line work is too thick. the characters are too stiff. here's a quick and dirty redline on one but it's semi hard to see what's going on due to jeph's highly saturated colors:
you'll note that basically the heads are FAR too large for the bodies. stylized or not, it makes them all look too tall and too thin. people have well defined hips and shoulders! if he wants to move quick and stylize, the easiest thing to do is to just EMPHASIZE these things instead of meshing them into the overall body. Jeph also needs to be more conscious of perspective, lighting and pose wise. Here
angus wil is in an impossible position (not to mention he looks like marten), but if his head is set lower and his shoulders set back, it just looks like he's leant over a table or whatever while sitting. a little dynamism in poses goes a long way. now that I reconsider, penny's right arm should be dropped and her hip out to the left. it'd be dynamic AND sexy, which is what jeph is ever going for by putting characters in underwear. which just btw it really seems like he loves fanservice lately. also something jeph can start doing is using variable line width: thicker lines for things that are close in the foreground or need emphasis (faces, for example), and using thinner lines on things in the background. speaking of backgrounds, using muted colors in the background will put larger emphasis on the characters in the foreground, causing them to pop out more and be more dynamic. try to use a muted base color and a muted shade, and somewhere in between the shading and base tones, throw in a more saturated color to give the colors some pop. it's a very basic way to do it but it's quick and works well. high contrast between lights and shadows is a great way to make things stand out, but that's something that you have to get a feel for through studies and can't really be considered a "pointer" as much as a "to-do."
so as you can see I clearly know what I'm talking about, because I've been doing model and color studies for a long, long time. god forbid I be 18. but I guess you're sitting too high on your high horse to let your warrior-god jeph take criticism and must find ways to pick me apart until only the vultures are left to desecrate my body.
and just to finalize the point that I know what i'm talking about and you're all being cocks, here is a
quick speedpaint I once did that I still really like.
edit: sorry. I just want to see jeph improve as an artist. he's been kinda stuck at a certain level of skill for a long time and it doesn't seem like anyone but himself calls him out. it's a little flustering.
