Skip the instances & their quests until you hit 80 (or can breeze through the instance.. like Nexus at 78 ). Just work on levels.. the rest (gear/gold/rep/etc) can be more easily done when you're 80. However, it's never too early to start the Sons of Hodir quest chain, as that'll have you doing dailies for 3 weeks for exalted.. which you need for shoulder enchants.