I hesitate to comment without having played V all that much yet, but....I recall the transition between III and IV taking me about 6-8 months before I really felt comfy with IV. I had ALOT of issues with IV, but learned that it was, in many ways, a much different game. Maybe not better, but different. And I believe, in my heart of hearts, that may just be the case for most people making the transition. Anyone who has been here for any length of time knows we will see improvements from Aaron, some more helpful than others.
I may not have as many issues with the UI as others as I use several of the keyboard shortcuts...and have a trackball rather than a regular mouse. And I've played IV to the point of my shoulder cramping from being in one spot all night. (ahh, to be young enough and free enough to play all night again..)
Anyway, I don't play much other than the SE series and some Paradox stuff (EU, HoI, etc). Both communities are (mostly) extremely civil, there is great support, but no one is ever really satisfied, and probably never will be - so get over it, and enjoy the game, or wait and enjoy it later.
Personally, I don't see me taking 6-8 months to make the move over to a majority of my playing time to V. I think I already like V better than I liked IV to start with. Just my 2 cents, for what it's worth. Maybe I'm just too much of a fanman (I'm too old to be a fanboy!) or maybe I just trust Aaron more than I did back then.