Seeing how many people complain that CoF is just a glorified Pinata of useless exalted items (I happen not to agree… not completely), I have a suggestion.
Based on a mechanism that you already have implemented, why not add a CoF bonus that allows some special crafting (maybe with a special rune/glyph).
Allow combining two items of the same type. Basically take two 4 affix exalted items, one in the forge and another equipped, put in the special rune (or glyph + shatter) and then magic happens:
A random number (min 1, max 4) of the affixes of the item in the forge replaces the same number of affixes of the equipped item (same slot of course), each affix keeping its level. Each affix has a chance of replacing one of the two affixes of the same type from the other item. The same affix slot cannot be replaced twice in the same forging. End result is one 0 forging capacity item where the affixes are a combination of 4 out of the previous 8 affixes.
Sometimes we might get lucky, imagine combining two T6 affix items and ending up with a 4 T6 affix. Given the randomness of it, it won’t happen very often, but maybe often enough to finally give one really nice item once in a while, requiring both effort (collecting enough exalted to try this a large number of times) as well as… luck.
This would open up the crafting and maybe add a little bit more excitement to CoF.
Example:
Item A: Pa1, Pa2, Sa1, Sa2
Item B: Pb1, Pb2, Sb1, Sb2
Item A and Item B are of the same type.
Pa1 can replace Pb1 or Pb2, Pa2 can replace Pb1 or Pb2, but no P can replace an S (prefix replaces prefix, suffix replaces suffix). Also, if Pa1 replaced any of the prefixes (Pb1 or Pb2) the same prefix cannot be replaced by Pa2, same for suffixes.
Result:
Item C (ex-Item B base): Pb1, Pa2, Sa2, Sb2, so Pa2 replaced Pb2, Sa2 replaced Sb1.
ETA: no double dipping of course (no 2xT6 Cast Speed). An affix would, if rolled to be transferred, automatically replace the same affix on the destination item - if such an affix exist.