i have a level 85 and i currently have 307 item level and I'm aiming to get at least 328 so i can do some heroics. i just reached 85 the other day, and don't do arenas much but i am making plans to do arenas in the future also. so should i keep questing for armor or... what?

I suggest you go to www.thottbot-legends.com and sign up for an account

Arenas will give you PvP armor, so don't bother with that if you're a PvE player. Grats on 85. Now, start queing for random dungeon. You'll get some armor drops from the randoms, plus you'll get justice points you can use to buy even better armor.

And yes, questing is good, too.