Its hard to get stones because there was no offhand weapon on floor 200 and the drop rate of offhand weapon with gold,max,suit stat on floor 160 and below is too low. I think its easier if the requirement for a stone is resolving 15 random items with stat(gold,max,suit) instead of resolving 1 of each parts.
To get offhand equipments, I go to dungeon level 8 or 10. The most difficult stone to get are the max stones, when I'm down to 1 requirement, I use bronze stones to hopefully grant me a max equipment attribute. The easiest are the gold stones. But all and all, stones are manageable. My issue is the result of using suit stones and regenerate stones. At least, grant us an opportunity to choose, when a stone is applied, a menu will appear showing 3 results that we can choose from. With this feature, hopefully we can avoid months of grinding.