[@Archmage MC]

[quote=@Archmage MC]
[@jynmi88]

I've got lots of knowledge about chemistry, so eventually everything short of the gasses she'd be able to make or control or however that works since they are technically 'earth' elements. The downside is, without the big 3, Hydrogen, Oxygen, or Nitrogen, alongside other gasses, there isn't much that can actually be made short of blocks of something. Gasses are FAR FAR more useful for explosive results or dangerous chemicals.

Guessing most of this would be after the 'awakening', IE past where One Piece is right now, short of basic carbon manipulation or stuff found in normal earth minus the gasses. I dunno, Logias are weird. Aokiji should be able to make explosives easy with ice but doesn't. The light guy should be able to make black holes but doesn't, ext...
[/quote]

Ah okay.  I can see where you going with you're character's devil fruit, and I think it should be okay if you hold off on the bigger things till the characters start awakening their devil fruits.  
All that's left is the character's position on the ship.  
Captain
First Mate
Sniper
Doctor
Cook
Navigator
Are taken.  
So off the top of my head that leaves
Ship-right
Cabin Boy
Musician 
but there could be something else if you think about it.