Hello Mustang
What ever the size of the wood chips, the "cup" (hole) has to be large enough that the chips can both enter (and most likely momentarily staged) and then "dropped". Filling these holes/cups with a somewhat consistent amount may prove to be tricky. Then add to the problem that this same revolving plate/disk/cylinder will need it's cup to "dump" into another "hole" (the entrance to the fire pot).
I've worked with industrial packaging system (volumetric fillers) where the "target" hole was elongated to maximize the time the fill cup passes over it (giving the product) a "longer" chance to dump/empty completely.
I'd suggest a "larger" diameter shorter "depth" rather than the other way.
Also keep in mind the need for some "adjustment" Be it adjusting the speed of the rotating plate/disk and/or some adjustment of the "cup" volume (by adjusting the depth of cup).
For my own (mostly un-started) project I keep coming up with more issues/problems than solutions. But NOT given up. There's a lot of "crap" being sold out there, and they want a lot of money for it. It shouldn't be real hard to build, once all the bugs are worked out.
Perhaps you should also consider how/where you will store the wood chips. (I know some who have used two tons of pellets in a season)
Been keeping my eye open for an old woodstove to use as a "prototype".
Keep chippin away!