Do a search on ASH and UNBURNT Coals (there are pics on here). You will have SOME unburnt coals and stuff that doesn't burn (Rocks, etc...) sometimes they ride along the sides, and never get burnt.
Yours should should look either greyish or reddish in color (Depending on the coal company), and sometimes clumpy (coal cakes) depending on how hot your are burning it.ASHESPictures of ash and qualityred ash or white ash
If you have a CoalTrol, what are you settings, MIN/MAX , etc...Baro Damper Calibrated correctly ?
The 1-2" of ash is correct at full burn, you can bump the MAX up so you have approx. 1" of ash without pushing hot coals off. Every stove is different, so the MAX for one person, is not the same for another, even with the same stove, because of mechanical and tolerance differences.
But sounds like it's working correctly.