Hello sory for my english,
I am interested more in the model and changing the emulation, but a question nagging me for some mind temp, I would like to get an answer before the breakthrough.

Is it possible to radically change the gameplay in world of warcraft?
Eg
       Add one-fourth talent tree
       -Radically changing the allocation system such talents as the game with allods ruby.


Example ruby on the game allods online.
Each lvl in addition to winning a talent point saves ruby to validate a checkbox.

And more generally through a client development Lua / XML interface for server and core (mangos) can add your new system?
Or the client imposes a limitation?

If the answer is positive the possibility deviene truly infinite.
-Game Store
Novel mechanism-
New location-equipment ...

Thank you for read,
cordially
Florian