It's not series director that should be to blame for the 1-episode-1-chapter pacing. It's TOEI ITSELF that ignores the One Piece TV.
Toei focus on Toriko, Precure and Seiya only. The One Piece staff are hard-working all the time. But they don't have enough money, and can't do anything they want to do, for example, making a 10-episode-long filler arc.
By the way, the new producer of One Piece TV, 櫻田博之 (Hiroyuki Sakurada), is a hard-working one. He's far away better that the last one, 柴田宏明. However, though proucer holds more rights of speech, there are a lot of things that they cannot decide.
Kind of sucks that Toei has that attitude. Do you know if the fans in Japan complain about it a lot, or do they just keep quiet about it because they know it's an unfixable thing.