What are your suggestions for a Gunslinger looking to play up the tinkerer/inventor aspect of being one of the heralds of firearms? I was planning on taking Master Craftsman and the two feats it allows to allow my Pistolero Tank engineer to improve his weapons...

1. Rapid reload
H1. Two-Weapon Fighting
3. ???
G4. ???
5. Master Craftsman
7. Craft arms/Armor
G8. Improved Two Weapon Fighting
9. Craft Wonderous Item

But I'm seeing both ITWF and Craft magic Arms/Armor arriving two levels late... Should I be worried?