So I'm nearing 78 on my new warlock farming toon and I was planning on waiting til 80 to start farming herbs and ores. Then I started thinking... Why? At 77 you get coldweather flying and you can start the quest chain to become neutral with Sons of Hodir. Why not finish that quest chain and simply start your farming? I can't think of any particular reason you HAVE to be 80 to have a farming toon. Would love to hear thoughts.
I started farming with my DK when he was 78, he's farming 24/7 and currently dinged to 79 The 2/3 levels doesnt make the char stronger or something, it still kills mobs like butter so i'd say go for it!