Not sure that this is necessarily a question yet. General Modeling
As I'm going through this (even though it's just the first of 3 parts), I'm getting a little more geometry than you are. For the most part I'm following what you're doing to the "T", but I'm also trying to see what's intuitive to myself as if I were doing it blind - I figure I'll learn by my mistakes. I'll try to post the model as I've got it and point out what could potentially be problems and how I'm trying to solve them. On (1) I was trying to get more detailed around the right eye. On (2) I was trying to keep the same flow as the bottom lip.
Not sure how it'll all turn out yet. We'll see.
LOL. And as part 1 ends you've eliminated my thought that I'd have a problem at (2). Number 1 should still be intersting.
Edit #2... oh dear god!! With that extra edge I wasn't able to fill the mouth with out a triangle, so I *sniff* added another edge at the bottome of the mouth and added a corresponding edge to the edge of the logo. Is this necessarily a bad thing?? I know it's just a simple model and the poly count can't get too bad, but is this a bad hait to be getting into? That's what bothers me. Everybody says less is better.
I'm thinking (3) to even out the topology on each side of the mouth. Yup... I'm looking to animate this puppy as part of the lip syncing stuff whenever I get there. Have I gone overboard?