Well there's really not much to comment on about your line art, it looks like you're spending too much time fussing over the lines. Actually start painting over your lines with color, and shade the volumes in with highlights and shadows (DON'T USE THE FILL TOOL TO COLOR THINGS WHEN YOU'RE STARTING, PLEASE). And look at the resources Pixelation has on color selection, they're good reads.
I'm just saying this because I've made the mistake of trying to make "perfect" lines, before shading colors. And then when I was satisfied with the lines, filling it in with color just looked terrible.
Anti-aliasing is something you do AFTER you've got your colors placed and you want to smooth out the details. Don't worry about that. Just post again when you have... more to actually make remarks on.