I am having the same issue. I have a 4cc band, but my fill is currently at 4.60 cc so I'm panicing that if I don't find my so called "sweet spot" soon, it will be over for me. I am finding that I still have to pay a lot of attention to how the food feels going down. Try to stop the second you feel that first signal of full. It doesn't really feel like "full" to me.
I appreciated the explanation as to what restriction really means, because I struggle with that too. When I got the band I was under the impression I would have automatic restriction, would take 3 bites and literally would not be able to fit anymore food in. Yeah, it doesn't work like that for me. You may need a fill though, you can't go totally by what the Dr. thinks. They told me at my first fill of 1.5 cc's that I was done and I could eat a horse. Hang in there and let us know what happens.