So, I found a 2D character template I liked (I was asking about copyright issues with a different template before) and decided to get to making some sprites. I looked at some deviantART and youtube tutorials and came up with these:

The template in question is here: http://opengameart.org/content/24x32-rpg-character-template

They look decent to me but I don't want a game where an artist plays and suddenly goes, "Look at that ugly shading, anti-aliasing, dithering, w/e!" Getting to a professional level is surely impossible for me (seeing as I can't even draw) but I'd like to at least get to a passable level where an artist would go, "Meh, at least it doesn't look like total shit."

I followed some tutorials but can't seem to apply the theories that they teach right. It's not that their explanations are crap, I get what they're saying. But I find it really hard to use those theories. The only thing I really managed to apply was to try and make my lines 1px wide.

Also, how long should a single sprite, like the ones above, take to make? Because I spend about 30 minutes to an hour for each single sprite.. Also, when making sprites, I tend to make the light source shine from the left as I try to shade. Any tips or tutorials on specifically shading character pixel sprites?