Energy powered weapons and armor?
What if there was pieces of equipment who's full potential can only be unlocked through energy? This doesn't need to be debilitating for free players either.
Say the max you can reach is level 5 on these special pieces of gear. To reach beyond that threshold, you need to imbue it with energy and thus allowing you to further level it to it's max level.
I'd recommend this being for weapons that have multi-stage charge up moves or armor and weapons with a higher than normal stat growth.
Imbuing energy could have multiple side affects to the game. I think that the bad would outway the good though. Players who do not have the option of buying energy would have to use their adventuring energy towards their weapons when the monster get tougher. Those who buy energy would be able to get way ahead and be way stronger than the free players. The developers probably dont want the game to become dependent on money. They could make it so you have to get certain materials to be able to power it up but its just not a good idea for now
Many games have tried that, never really works out without pissing a lot of people off
This is already basically in effect with upgrade progressions such as troika->khorovod, prismatech->mk I->mk II. You pay crowns,energy and materials, and get a more advanced version of a weapon/armour you already have.
C'mon guys, lets suggest some things that aren't in the game already :P
I think, the current state of the game doesn't require gear THAT powerful.
That and since you're already paying to find items and craft items, paying to upgrade them might be considered a little outlandish.
I won't argue if they do end up doing this, but there are better methods they could employ that don't require directly paying to upgrade the item's potential.