I have an idea for a Marine...I just need the yay or nay if it sounds good:
Myra Olejo:
Myra is a captain of the Marine forces, on the sleepy island of Isle de Volcan, a long island with two small but active volcanoes. It resides on the Grand Line. While quite lazy most of the time, she truly does show concern for the citizens and often defeats any visiting pirates that cause problems. However, she doesn't look at the difference between Marines and pirates simply because of their professions...but rather as one being a good person or bad. If a pirate with peaceful intentions shows up, she ignores it, despite her duty to apprehend any and all criminals on the island. Some people protest to her slack attitude...but she does mean well.
Her strength comes from her upbringing and martial arts style. She uses the martial arts style Dao Dan Do (previously used with my old character Asa) and her primary weapon is a pair of naginata...an odd combo of blades and brunt force. She learned the basic Rokushiki techniques from her childhood with the future members of the CP9 (Lucci, Kaku and the others as children) but left from conflicting differences. While the other kids were looking at serious, high level positions, Myra simply sought to take it easy. She sometimes uses Rokushiki, but prefers not to, saying its "Too much hassle". One of her personal favorite tactics, and one of her quotes, is : "Just keep hitting it until it quits."
However, as the call for more Marines on the sea pull Myra away from the simple life...it'll take more than brute strength to live an easy life.

I was thinking she'd get involved with Matsu, him being a Shichibukai. Something along the lines of "keeping the peace," should he get outta line. It's not likely since he's a good guy, but still. Someone's gotta do it.