Reboot world discussion and tips

What is the benefit of crafting in reboot? What can you craft that you can't get elsewhere? (I've never really done much crafting)

As an alchemist, you can craft a variety of buff potions (provided you can get the recipe and materials). You can also fuse equipment in an attempt to get useful potential on it. Not sure that's cost-effective.
As a smith you can craft androids and their hearts, which are not otherwise obtainable. Not sure how useful that is, considering that the hearts are all temporary and even if they were permanent you can't scroll them, they can only have 5 stars, and their potential is tier 1. You can also craft other gear but I think the items that drop, even from normal monsters, are generally better.
As a jewelsmith (accessory crafter) you can, well, make accessories. Depending on how hard the ordinary bosses (Zakum, HT, Pink Bean, Easy Magnus) are to defeat, this may or may not be of any use.