I'm not going to start from scratch again, but I'm going to go back and edit certain areas. Luckily the freckles are on their own layer, so it shouldn't be too hard to change the lighting on Fiona's skin underneath. I can dodge/paint over the hand to get it lighter, and Sha's head will be a simple select-and-scale.

It took me a long time to get relatively comfortable with a Wacom. I could show you all kinds of crappy matte paintings I did before I got a handle on it. I borrowed someone's tablet PC to draw with once, and it was pretty awesome, but that by itself wasn't enough - there were a bunch of things that I needed to get straight before a regular tablet worked as an artistic medium.
- Tablet size: Mine is 7x9 (I think). Much smaller than that and it becomes impossible to get good line control. I've worked with as small as 4x5 and it was practically unusable for drawing.
- Pressure sensitivity: You need it. If your drivers are fucked up, or your system software or tablet are old, it might not work, taking a whole critical dimension out of your brushes.
- Photoshop brushes: Are important. The basic ones that come with the software don't come near to tapping the possibilities. If you can't find any to download, I could send you my set.
- Working technique: This one didn't click until I started going to the live figure drawing sessions in the computer lab at work, and watching how the professional concept artists did it. Not sure how you could get the same effect; maybe by watching step-by-step video tutorials from matte painters, and by trying some paintings from life instead of from photos.

You should post some of your oils sometime. I think I've only ever seen your drawings.