Subcrafts for Armorer?

[animeprime]

I'm thinking of making armorer my main craft to help with my melee jobs but it looks like you need a good number of subcrafts. Assuming you reach rank 50 with ARM which subcrafts are beneficial and about what level do you want with them? A long time ago I heard you want most to at least level twenty but some are more needed than others like weaver for body armor or carpenter for shields.