It's a good idea to not let your gear's level lag your hero's level too much. I've been crafting armor every 6 levels for non-vet PvP and it's been just fine.
Some people will tell you that you can't compete unless you make purple gear every 2 levels... these people are wrong.
As far as vet PvP goes... I can't help you.
When you hit v16 and still have your v15 gear, and lose battle levelling, that's when the pain really begins