Is this how it works?
Lv4 Gem = Lv1 Rare gem
Lv5 Gem = Lv2 Rare gem = Lv1 Epic gem
Lv6 Gem = Lv3 Rare gem = Lv2 Epic gem
Or this
Lv4 Gem = x
Lv5 Gem = Lv1 Rare gem
Lv6 Gem = Lv2 Rare gem = Lv1 Epic Gem
N/A Gem = Lv3 Rare gem = Lv2 Epic gem
Because if it's the second then without question that's Pay to Win (But thanks to the failrate of higher gems it's already P2W). I expect Gems to have more adjustments since they're new but you should have a guideline for how you plan about using them for the server, in terms of fairness to the other players. The luckybox items are already OP for luck which is already P2W.