Alts are great but I enjoy my main. I have put time into getting valor ranks, gear, crafting etc for my main. In addition, I am not asking for AC dual spec. Just a dual spec within my current AC which I love so I can more easily switch between the two roles my AC offers.
Also not everyone has time to invest in leveling up alts. With the legacy system adding more character options I am not even sure I want to put a lot of time into alts until the details of the system are revealed.