Firelands Daily Quest Guide

http://www.icy-veins.com/firelands-daily-quests

Here's a quote further into the link about who to choose after you get your 150 marks if you want to open the vendors first:

If you want to unlock the vendors as fast as possible, desire to spend little time questing, and are not in a hurry to obtain the Veteran of the Molten Front meta-achievement, then we advise you to do the following:

recruit the Shadow Wardens;
recruit the Druids of the Talon and do their daily quests once, the day you recruit them;
go back to doing the daily quests from the Shadow Wardens until the end of the event;
recruit the ancients;
recruit an armorer;
fill the moonwell.