Gratz! #1 thing if you haven't already: train Wisdom of the Four Winds from the flight trainer at the Shrine of Seven Stars.
Scenarios are another option along with the heroics, it's another way to grind Valor but I'm not sure yet how many provide worthwhile gear. You can continue questing through Dread Wastes while waiting for queues and eventually receive some 450 gear, and you might try joining a Sha of Anger group sometime.
Right now I'd suggest running Arena of Annihilation for a 450 weapon, and visit Ao Pye in Townlong for a nice neck upgrade when you can afford it (wowhead.com/npc=70346). I think Striker's Battletags
is what you'd want. Isle of Thunder might feel tough at first, but should get easier as your gear improves. (edit) Also, I forget exactly how it works but there's at least one daily or set of dailies for which you can choose to do either PvE or PvP content each day, so a bit of extra Honor is available there too.
If you don't mind running a lot of dailies, Klaxxi and Golden Lotus vendors will have gear, and reaching Revered with GL unlocks Shado-Pan and August Celestials for more gear, but as mentioned, it's mostly yet another way to obtain gear. You can look up each of those factions at Wowhead to see what their quartermasters sell, and what to expect from the rep grinds (in my experience Klaxxi went pretty fast, GL didn't).
And if you need a break from grinding for gear, you can run older content for achievements or whatever, work on your professions, or maybe do Angler, Tiller, and Cloud Serpent dailies.