I believe Oda has made the right decision with his intention of focusing on the Curly Hats, particularly Sanji in the coming year.
As far as the story goes, Sanji has always been a mysterious character, in the sense that his identity has not been fully revealed. We only know him as Sanji and his current ability/skills as "Black Leg", a good cook, etc. Of course we do know some parts of his past when he was trained to be a cook at one point. However, with the present ambiguous wanted poster, it triggers our thoughts to think who he really is.
I have always thought that Sanji is pretty unique, particularly when I look at his facial features such as his eye brows. Even the way he calls himself gives me an idea that he isn't just an ordinary young man who has learned how to cook and becomes a chef afterwards. Additionally his rare blood type also gives away some hint of his unusual heritage.
As Oda announced his intention for 2016 with Sanji as the focus, I would love to see Sanji's background be told. Perhaps coupled with some past history of him, for example his childhood and how he got separated from his family. One of things that Sanji has hardly (or never) talked about is his family, like who they are. Most of the characters, it has been pretty clear where they come from. Luffy has Garp as his grandfather, Ace and Sabo as his swords-brothers; Nami has her hometown of families (her village people are like family to her), adopted mother and sister, and so on. Hence, it appears that Sanji's heritage may be important in the forthcoming story.
As for the other characters, I'm seeing some interesting DF skills from Brook, who has displayed quite a fair bit in the recent chapters, though it appears to be like a "glimpse" of it. Nevertheless, Brook's past was a very sad one. I particularly like the song that he sung when his crew mates dropped dead one after another, and it made me cry a lot. In the coming year, I do hope to see how he progresses and how he uses his "upgraded" skills to help the other Straw-Hat members in times of crisis. In fact we are seeing him displaying gradually and hoping to see more of him.
On the part of his heritage, I can't help but think of Laboon. This is one whale which I am fond of. I do hope to see more intimate moments of those past and perhaps, how he became a pirate (in his former crew).
Next is Chopper. In the current chapter (811), we are seeing him helping out as a medical doctor. He has exercised his authority as a doctor and displayed good medical traits as a healthcare worker. In the aftermath of an island being destroyed and people in the brink of death, Chopper remains calm. Recall what Chopper said about the Minks who had inhaled the poisonous gas. He mentioned that any delayed treatment would have caused permanent damage to the people's life. Perhaps some may even die from it. Therefore in this instance, Chopper has really displayed how well he is as a doctor. That also shows how caring and responsible a doctor he is. In our real world, we do need such doctors around, don't we?
I suppose it would be nice to see how far Chopper has advanced in his medical skills, and of course, being a DF user, I would love to see how skillful he has become. Some interesting new skills beyond his "monster point" perhaps?
The next one is Nami. I haven't seen her much in her ability, but she has displayed pretty good in providing emotional support to the Minks, especially to Wanda. Wanda seems to be in so much stress and being an important person to the kings, she is shouldering a great deal of responsibility, particularly in ensuring the safety and well-being of the kings.
On the part of Nami's ability, it would be nice to see her displaying some interesting tricks in controlling the weather. Perhaps something about her navigation skill is good too.
As for the rest of the Straw-Hats, I believe it would be natural for them to get better. For example, Luffy would need to overcome the limitation of his 4th gear; Robin may need some screen time to shine. In fact, I find her DF skill very interesting and it has a lot of potential to have more upgrades. I wonder if Oda would consider giving her though it seems like she is acting as a supporting role. Though having said that, I'm impressed with her when she protected Rebecca in Dressrosa and how she gained the trust from Kyros and took the responsibility in ensuring the young girl's safety, so that her father could fight with Diamante without worries. At the end of it, Robin sustained quite a heavy injury. Amazingly she did not even uttered a word or screamed out due to the pain. She was also seen to be bleeding very badly. Yet, she continued to protect Rebecca. She gives me the impression of how a mother would have protected her children. I salute her for the kindness.
From the progression of One Piece story, it would appear that the Zou arc will continue for perhaps another 1 1/2 to 2 years, or even longer. So Sanji and team would presumably be the centre of the story before any great war breaks out.
With the above said, I have always thought that it would be nice to have short stories of the characters of their own. It's like Fairy Tail for example. A spin-off story is always welcomed to bring out the biography of a particularly person or a group of people. Of course this is only a thought from me.
