By constantly doing quests, you will experience a very different game than if you just level through pure grinding. You'll be out there making a contribution towards the Alliance or the Horde. Doing these quests takes you through the heart of the game's story AND provides the fastest rate of experience. Have fun in World of Warcraft and enjoy developing your hero - your adventures will gain you great reputation amongst the land.
This expansion suffers from the Warlords of Draenor (WoD) effect, initially, players will think this is a great expansion but upon investing some time into the game they'll realize this game is a disaster. The pre-patch should have been our first warning with how poorly designed and executed that fiasco was, but beyond that, let's look at what the expansion itself offers:
I recommend not counting on transmog sells for your monthly gametime. Its a great market, but also pretty random. You have to have the right items posted at the right moment if a player needs a certain item. If this is not the case, of course you will not sell anything to him. There are people making millions of golds a month with transmog. But they are very professional at it and it really takes a lot of time.
Chilled to the Bone, Dampened Magic, Kleptomania, Netherwind Armor, Prismatic Cloak, and Temporal Shield have limited use in PvE content in terms of increasing your damage in the open world, but they can be situationally useful. Notably Temporal Shield can be utilized for, functionally, an extra 6 seconds of combat time against large elite mobs.