This is what Evon Gnashblade is surely missing in his business:)
I suggest that pvp’ers don’t buy that much gemstore stuff as pve-only players do, but this is also true because there ain’t much of it at the moment in the gemstore.
Here’s my list of suggestions:
Various finishers or even endless finishers.
New special item to be used in PvP mystic forge to get a 1-slot stack of 100+ pvp salvage kits.
PvP template/build slots
Cosmetic weapon enchants (permanent unlock) with a new section in pvp locker to draw them from (they are added to the locker just as you purchase them, and can be withdrawed as many times as you want)
What would YOU like to have available in the gemstore for pvp reasons?