A Fragile Immortality
Generally crafting is something done during downtime, and isn’t much fun as we’re just rolling dice running against the extended action limit. Therefore, what crafting will allow one to do is add a benefit for each additional five successes.
Benefits are fairly freeform, but a single increase to the stat of an item; or 9-again in broad, but not universal terms, or 8-again in narrow terms. Work these out with your GM. He’s a nice guy, flexible too from what I hear.