I think the PEN shop should be a bit more important as a whole. There's no reason to use PEN right now other than by enchanting, gambling, or to abuse the Buff system in game, and sometimes buy that skill that isn't available perm..(I'm looking at you SP Mastery).
Way back in the Beta days, you could buy items perm outright from the PEN shop. These items should cost a lot more than the 30-Hour duration versions. A perm item is always better than a timed one, and now especially since there's no more repairs. There're specific items that you can't get perm in game that is available for PEN on a duration, and that's just annoying. Add a "Unlimited Use" duration selection to items in the PEN shop. As for the costs I'd imagine something like this~
10k: Hair, Face, Accessories, Gloves, Shoes
20k: Shirts, Pants, Pets
Of course though for the Pets they'd all be statless versions, and just for cosmetic purposes. They could still be enchanted however so they wouldn't be completely useless. They should be their non-fp skin versions, and maybe only the older pets should be available. I don't like how you can't buy them with PEN at the moment. Also how come there're never more PEN stated clothes added to the shop? Why only accessories Hair, and Faces? They may not be FP stat but some of us we'd like to preview our "look" in action before we dive in to buy the FP versions. xD
As for skills I also think Dual Mastery should be available for PEN now since we have a premium version in game.
Why would this be a good thing? Well~
I: It'd make the PEN shop a little more worth using, (especially by newer players).
II: Buy-able PEN stat perms would make getting Gears, Cells & Cores much easier, (think of the newer players. This would be good for them).
III: Some players like to play PEN only stats, and this would satisfy them a bit.
IV: It wouldn't hurt the AP stat shop because AP is still clearly more powerful.
V: If we ever get that No Stat mode, these items would be just as viable.
Bonus: Why roman numerals? I love them. C8