First off, leveling a second class is extremely fast, but I agree it is boring and needs a lot of work.

Second, we don't need skill trees. They are a ton of work for devs, and a little work for number crunchers only to end up with everyone being forced into specific specs for those number crunchers delight. Even WoW has essentially removed its skill trees. When we have more jobs branching off each class, we will have more variety. Kind of like sch and smn, both are same base class but act like a different "spec" in other mmos. We have *some* class customization with cross class skills, but ultimately this way is far easier to balance and allows devs to spend much more time on content and new jobs/classes then pondering the possible ramifications of an extra 2% damage how elitist might stack it.

tldr; Talent trees are illusion of customization and take away a lot of dev time, more jobs off current classes is the better option.