Originally Posted by
Wilfire
Ask for better class balance and funner class mechanics.
Every time Blizzard adds a new class, all of the other classes get shat on and have to be redesigned to keep up with the new class' mechanics. Or worse, become unviable. Take DHs for example. Before DHs, some classes (namely monks) had crazy mobility but it was not anywhere near as outrageous as what DHs can do. Thanks to DHs, many more classes can zoom around the map now like it's some mock parody of a Japanese ARPG. And in case of BGs, every other tank class has become unviable because they don't have the insane utility and mobility of DHs.
Or take DKs for example. Remember how they completely ruined clever positioning in BGs because they could just grip people from 30 yards away? Blizzard followed up by giving all classes crazy grips and/or knockbacks.
The takeaway is that if they use a new class as the main draw of an expansion, they have to make it distinct and overpowered enough to make people want to play it. And they do that by giving it new, idiotically overpowered mechanics. If they introduce tinkers or dark rangers, I can guarantee you that they will be the bane of PvP and most likely the bane of PvE as well (at least until they get brought in line with other classes in 2 years).
Ask for improvements for existing classes instead. Ask for an expansion in which all classes are viable for all types of content. Ask for an expansion in which frustrating class mechanics don't make you want to bash your head against a wall. A shiny new OP class won't make you any happier in the log run.