I can identify. My preference when writing is to reveal surface only when portraying a scene, reserving dips into the minds of POV characters only once in a very great while. Mariann's been pushing me to change that, and incorporate more interior monologue into my work. Whenever I do that, though, I feel as though I'm falling into some kind of writerly trap, as the sensation of writing that internal POV stuff just doesn't seem RIGHT.

The only real test of your work will come when someone else reads it, which you probably already know. You may simply be self-conscious about your work, and that leads to the idea that it's "stiff" or otherwise lacking. Best to get some feedback before doing anything truly radical, because you might be worried for nothing.

I've noticed a lot of writers have a particular POV that they consider the best for them. I try to figure out the best POV for the story... (Dunno how successful I am, but I try.)

I am constantly amazed at how, one is supposed to, you know, GROW as a writer. That it gets harder, not easier, because you have to keep pushing yourself. I do have one POV that works for me. . . and now it's time to push a little bit -- and find, as you say, the POV that works best for the story.