What does your ash look like? Are there little black coals or just powder? When I empty every 2-3 weeks, it is absolutely full of ash. Almost packed. But, that ensures I get all the heat out of it i can. Those black coals are heat you're throwing out. I COULD pull a full ash pan out every week (in fact I used to do that), but again, there would be coals in it. When you let your ash pan fill up a bit, it will pull that hot spot back away from the door. I get that same hot spot for a few days after emptying, but it gradually works its way back as the pan fills up again.
As far as smoke goes, with the cold temps we're having, I'm noticing a bit more really white smoke. I think that is moisture from the wood that's really only visible in the extreme cold. When the temps are a bit warmer, I do have less smoke. Almost none. It also depends on the wood I'm burning. How seasoned is your oak? I have oak that was cut in July and it smokes a lot more than the other wood I have. From what I gather on here, it takes almost 2-3 years to get oak down to a good moisture content.