I use World's Best because it doesn't have a lot of additives. I put a bit of regular baking soda (not the stuff that is sold to keep litter boxes fresh) in with it. That seems to work just fine. I know what you mean about the pine pellets. They aren't the best.

I have a Rabbit Air purifier for my allergic dog. It is supposed to neutralize odors too, but I notice that it only comes on strongly when DH walks by with cologne. Normal household odors don't seem to make it react.