Either a humidifier type thing before the air enters the grill or a mister that would spray a fine mist periodically, or even some combination of both. A pan of water just does not put enough humidity into the pit.

This is a very interesting idea.  I do cured/dried meats and have a very handy humidifier that I could pipe up to the air intake on my pellet grill.  Will have to give this a shot on the next cook.

I also like the idea of direct flame cooking, but honestly my lil' Davy Crockett does a fine job as is.  I'd like to see a below-the-grate exhaust too.  I cook on a stickburner like that and it works really well, although it does make that end of the grill hotter.

 I would think igniter life should be an area to improve upon.  As there are so many manufacturers out there competing, features can't help but be more commonplace as well as new ones..Heavens, lights, some gassers have light-up everything. The list goes on.

The ignitor problems have been resolved with the new ceramic starters.  See video at Blaz'n website.  Mark claims extensive testing with no burnout.  Blaz'n and several others now use the ceramics as original equip. Unfortunately, there is no retrofit avail, since it requires a different aperture in the fire pot for the starter.

The only advance I want is ability to smoke at temperatures between say 120F and 180F all  year long, with ease and reliability...      In the main chamber of a pellet grill..

So I effectively want a pellet grill with a firepot and auger system that can stay burning , and only add about 50F additional heat above ambient conditions. And produces 'clean' smoke  while doing it...

I have to agree with you...make a pellet smoker with the firepot truly separated from the cooking chamber, like an offset stick burner and add cold smoking to the list of capabilities.

Like a Fast Eddy FEC120 convection smoker? And cold smoking on any an FEC100 or 120 is easy, just add a tray of ice to the bottom shelf and put in the cold smoke shelf.

Either a humidifier type thing before the air enters the grill or a mister that would spray a fine mist periodically, or even some combination of both. A pan of water just does not put enough humidity into the pit.

This is a very interesting idea.  I do cured/dried meats and have a very handy humidifier that I could pipe up to the air intake on my pellet grill.  Will have to give this a shot on the next cook.

I also like the idea of direct flame cooking, but honestly my lil' Davy Crockett does a fine job as is.  I'd like to see a below-the-grate exhaust too.  I cook on a stickburner like that and it works really well, although it does make that end of the grill hotter.

Something like this could be plumbed in fairly easily and adjusted with a ball valve and water timer
https://goo.gl/dPSKDi

With copper line and brass heads...

I wish my PG 1000 had wifi, the ability to run the fan after shut down, and maybe a variable fan as well.
Regarding the Yoder - are they still using 2 fans- mounted inline?

I just feel that the fan in the Yoder runs to fast.  I would like a bit more smoke flavor and thought if you slowed the fan speed downn a bit and let the smoke linger a while longer, whatever it is you were smoking would pick up more flavor.  Just my thoughts.  Would be interesting to experiment with.  If I were handier I know that this is something not all that difficult or complicated to do yourself.

Current Yoder's have 2 fans. It would be easy to put a switch inline of the first fan and turn it off and on at will. Or you could even  put a second controller on the first fan to run it on/off/intermittently, depending on what you are wanting to do.