Ciogli, great post.
Definitely a lot ot ponder here, and as I read through these old TUC posts, I'm notice a theme. Most people realizing that while Esmenet might not have been the most interesting character, she did end up having a ridiuclously significant impact on the story. Though this is mainly through the birth of children, its still significant.
I'm not sure if this was intentional by Bakker or not, but it seems almost every important woman in the story had an important, world-altering, chosen one child. The only one that does not is Serwa, who I guess was supposed to be too busy being a badass Grandmaster Mage-Monk to be bothered... But with this thought in mind, I wonder if she, too, had a special child with a greater role to play in later books.
Regarding the rest of your post, its difficult to ferret out a single reason why people disliked the novel or the series. As time has passed, I've seen a lot of different reasons, not all of which can be explained as people expecting an ending they didn't get. Some, maybe, but not all.
Definitely though, a concluding story would be most welcome, seeing as how we ended up with more loose ends at the end of TUC/TAE than one might be prone to expect. I hope some day we get that story.