One of my students is currently working on changing her right hand position to get better accuracy and tone. Changing one's right hand position is not something that should be taken lightly. Generally students will naturally fall into a position that is comfortable and relaxed, and that works fine. You have to have three key points:
1.) Fingers anchored on the head (at least one, either pinky or ring, is OK).
2.) Wrist arched. It should look like a bridge.
3.) Forearm resting on the armrest. It's what it's there for.
Outside of those criteria, there is a lot of variation in how people's hands look. The most important thing is that you are striking the string right down the middle of the pick (it should wear a shiny place). Also, your hand should not have any tension in it, and your fingers should not be flying all over the place; they should stay reasonably curled.
Changing your position after you've been playing a while is a huge undertaking and should be approached cautiously. Like I told my student, play everything slow. Play nothing fast until your new position is well established, or you will immediately revert back to your old position. Make sure you play through ALL of your old material with this new position. And do not introduce any tension into your hand, wrist, or arm, even if you think it looks/sounds better. It will hurt your playing in the long run.