My Fox Vanilla is my favorite fork ever too, I have been very impressed with Fox's products. I have a Fox Float on the rear of my race bike as well.
I wouldn't sell it for more travel if it were mine. By the way, if you think adding air to increase upward travel (decreased sag) you are thinking in the wrong terms for suspension. Sag in the proper amount is very important. If you take it to the extreme (for example, with zero sag), you might have more upward travel in your fork but you will also have zero downward travel, that sag is desgined so that your fork will have a little downward travel when you hit a hole or catch some air. A fork with too little sag will feel harsh and the sag that is designed into the suspension is an important setting. Try it both ways sometimes and you will see.