In all honesty 15$ a month isn't to bad, i mean i have to pay 30$ a month for my internet on my phone, but its just like getting 2 number 12's at burger king once a month except wow you saver it for a month and the meals are done in about 15 mins.
As for the char. select, you can always try out the char's and see which one you like the most and if someone uses the recruit the friend method from wow you can gain 30 lvl's right off the bat and see how each class plays almost halfway to the max lvl to get you a better view of the class. Instead of making a new char. and only having 5 moves with no gear, money, or skills.
Also if you guys have any questions about the game feel free to ask i no quite a few things and i would be more than willing to answer them for you.