Are arrows becoming a 1:1 ratio per synth?

[Reika]

I'd expect it to stay the same, it'd be pretty mind-boggingly annoying to have to craft one arrow at a time.

However if it is correct always remember you can buy 999 arrows for 50 GC seals

However, you wouldn't want to use just low rank arrows after the patch, since this is also the patch that makes stats matter.