First of all, I pretty much despise the idea of implementing Ogres into the mod. The only mention of Ogres is, when Bilbo remembers fairy-tales during the riddling with Gollum.
So this creature is pretty much made up by the movies, because they wanted to implement as much stuff as they could instead of focussing on the lore, what I would have prefered.
As I view it, Ogres are just another name for Trolls or a special Troll-race. In my interpretation they are similar to Hill-Trolls...
About the Stone-Trolls: I found PJs interpretation of Bill, Tom and Bert a bit boring, because as you said they seemed like just a bit more intelligent Cave-Trolls. For that reason I don´t find it that big a problem to just give them a different design as Bill, Tom and Bert.
It is not a fact, but more a suggestion, that Bill, Tom and Bert are Stone-Trolls. That´s all what tolkien-gateway has about them:
Stone-trolls were a race of trolls in the service of Sauron. Not much is known of these creatures, except that they inhabited the Westlands of Middle-earth and that they spoke a "debased form of the Common Speech". It is possible that they were not actually living beings, but mere counterfeits made by Melkor, and they would return to their stone images once exposed to the light of the Sun.
Bert, Tom, and Bill — the trolls encountered by Bilbo Baggins and his companions on their journey to Erebor — were likely of this kind, as they spoke Westron.
The reason I implemented them was to replace Mountain Giants as a robust long-rage siege-unit, which is totally missing in your suggestion, but in my oppinion the most important one of the three.
The thing is, that the Troll-camp is supposed to be an alternative for the Dragon-lair, so it needs to give you a somewhat equal benefit. So I think 3 different Troll-versions plus a hero (BIll, Tom and Bert) is fine.
Cave-Trolls should be the only Troll-unit accessable without an outpost.
The Snow-Trolls are the least important part of the suggestion and I´m not a huge fan of their EA-design either, but find it still a lot better, than the WarCraft-Hill-Trolls...
I just found it a nice opportunity to implement those and give them a usefull role, but if more people don´t like them this part can be removed or they could take the role of the Stone-Trolls with a different design.
The biggest problem of this discussion is, that everybody has different imaginations of the different Trolls, because the lore is so unclear about them. But as I said, this is also a huge chance...
Concerning Gundabad: When I remember it right, the team didn´t say they don´t like the style of Gundabad, but find it difficult to base a design on this short look we got from the movie. As I have shown there are other mods who made it possible and it looks a lot better than the EA-design, which is the worst in my oppinion. Espacially this dragondesign treasure-store looks very childish and unfitting for Gundabad...
PS: I didn´t like many Warhammer- or WarCraft-style in the Hobbit-movies aswell (especially the Trolls with blade-arms and all that stuff), but there are also a lot of cool designs so I think one must look at every design with no prejudice.
PPS: It is very difficult to base Smaug on the lore, because there is almost none information how he looked like and how many legs he had...
I find the four limb interpretation a lot more realistic, than the six limb-one, but am not stubborn about it aswell. If the majority of the community or the team likes another interpretation more, I´m fine with it, as long as Smaug get´s the place he deserves being a huge monster with enormous power. The only thing which is made clear about him is, that he was very big, stretching from one wall to the other and he is more compared to a force of nature, than to anything else, that means he has to be very powerfull aswell...