Sound good!
Just more to add more details on that
I guess your idea of re-roll are:
after re-roll...only the effect and dual change and all other things (effect grade, Dual grade and items nature) remain unchanged
(For example, D3 LG will still be d3 after re-roll, G7 LG will still become G7 with different effect and Hat will still be hat (robe will still be robe))
Correct me if I am in a wrong direction.
For the effect re-roll, just wonder will it be good to have a completely random effect re-roll or does it make the re-roll effect according to the Category (more details please look at HELP in game Legend Item 2/3).
So the re-roll effect only randomly select within the same category
For example, for warrior Legend Category I (15%), if you re-roll your d2 G7 Desire one, the effect will only be either D2 G7 Strike or Evasion.