Oh it would be very optimistic of us to Believe that the capital will release in any state that can be considered complete. If anything, once it finally comes out i can see 1 maybe even 2 years of updates dedicated to fleshing out the Capital and its many interactions with other characters.
I would guess the biggest reason why the creator would flesh out so many things before actually giving access to the capital (Seriously we got an entire new Village just when it looked like we were getting into the capital) its very much about the daunting task of creating something that can compare to what has been hyped up. Something something, first steps are always hard