You've gotten good advice on solving the coaling problem, but one last time, please, do not dump coals into, "The cellar ... with a dirt floor (that) could probably take many years of ash dispersal", if that's what you're contemplating. The old-school ash dump you envy was probably serving an old-school appliance that produced mostly ash dust, with rare coals. Just search up the many people who have been injured or died by using BBQ to heat their house, or cook with it in an unventilated manner. Dumping your excess coals (if that's what you're thinking) into the cellar is pretty much the same thing as lighting up a "hibachi" in your cellar, and is just asking for a CO disaster. You could create an oxygen deficient and/or CO rich atmosphere in your home, or maybe only in your cellar, and it could last for quite a while after your fire goes out, even though you might not see it on a detector at the living level.That is why I noticed the mountain of hot coals in the stove and looked for a solution. Aside from the coals issue, I think it would be very convenient to have an ash dump. The wife and I are pensioners, not getting any younger, and taking out the bucket of ashes every few days is a task that I would not miss, lol. I have been advised here on this forum that I might stoke the coals a bit and refrain from adding in logs until really necessary and thus not build up a mountain of hot coals. It seems to me that this might be my answer.
On a lighter note: If I sent you a book of stamps, would you send me your excess coals??
I had to be away for about 8 hours today, so I loaded my Kuuma (not stuffed, and not the good wood - it's only October!), to deal with the dark snowy days with highs and lows in the 20's, but when I got back, there weren't as many coals left as I would have liked, and the stove was in the irritating (to me) coal burn - wide open mode. It would be nice to add wood, but that would make it harder to get to the desired reload time around 11pm (as that would be pretty certain to get me to the morning with a good bed to reload on), but if I do, it will contribute to the burndown of the existing coals, maybe making this evening's load, a restart. Sucks to burn mostly pine - no coals!
The point of all that is: There are going to be variations in output in wood heat. It's just the nature of the beast. Between now and 11pm, I'm going to wish it was a little warmer. Probably around 3-4am, I'm going to wish my heater wasn't so effective. In the morning, I'm probably going to wish my master bath was a little warmer. Use the good advice, turn up the air as you get to the end of the cycle, stir the coals, add flashy wood to help burn them down, or deal with the natural variation in output (Flannel quilted shirt? I'm wearing one.). If you find that doesn't work for you, the solution to maintaining a constant temperature is a fuel source that's switchable and available for immediate dispatch - electric, gas, etc.
A radiant "dish" electric space heater, though rather crude, goes a long way in bridging the vital gaps in my house when it's really cold, and that might be a thought for you.
Please, whatever you decide, don't have hot coals anywhere inside your home envelope, unless contained in an appliance.
And, thanks for the inadvertent tip. I've been looking for a small stove that would run long periods at a low output without needing a cold start frequently, to replace my supplemental "fireplace". I'll be researching that stove.