Why we don't have 1 tree of mastery for each role?

Why do we have only 3. THere are tons of problem right now. Why assassins are in the same tier as utility suppots in the cunning tree? it doesn't make any sense, it gives 0 choices as much as before you jsut take what's good for one role or the other!

Control mages have 0 choices in masteryes because in ferocity all you can pick as a mage is the right keystone mastery dat gives little dot on spoells (but less effective for Aoe, wich is what mages do). So whats the point 0 choice there too.

THe only real tree i find compelling is the tank one where you can actually choose what you want to do. For the rest you have to create 1 separate tree of masteries for each role, and fill that with masteries.

Example: 1 tree for ap, 1 tree for AD, 1 tree for support, 1 tree for tank, 1 tree for jungle

That's it it's the only way to create meaningful choices regardingyour role.