Going Back, Unresolved Plot Lines
Up until volume 25 the series was fairly fast paced and many plot elements and characters were introduced. All of the "arcs" only lasted a couple of volumes and even the big arc against Baroque Works was divided into different chunks until arriving at Arabasta. However from then on the major arcs, Skypier and Water 7, became more drawn out and Oda has not touched much at all on all the action that was going on previous.
I'm not really upset about it really, but just super anxious. I have enjoyed the last 200 chapters and they retain the same charm and storytelling style that Oda has kept up all along. It just seems a shame to have left all that was building up to that point.
In terms of the timeline I can see it justified. From chapter 188 (volume 26) till 388 (present) I think only a couple weeks have passed, if not less somehow. I think all of Skypier was only a couple of days, maybe a week. Davy Back Fight I think was only a single day and Water 7 till now has also only been a couple days of time. Of course Oda could adjust the sailing time and whatever any way he wants.
I'm really hoping after this current arc is resolved we get to go back to the other dramas going on around the Grand Line.
The meeting between Shanks and White Beard.
What Black Beard is doing.
Long Term Issues
The friggin' meaning of "D" and how all the characters are related.
Who Dragon is and what are his goals.
Anyone care to add more, discuss?