I was wondering if a new video::EMT_ setMaterialType with the ability to use the Alpha channel could be added that could display textures in an order not dependant on the distance between the center of nodes to the active camera. I don't know if this the correct term, but my friend is suggesting that is sorting by layers rather than give priority to the node that has its center point closest to the active camera.
If this made no sense it was discussed in greater detail at this forum thread:
http://irrlicht.sourceforge.net/forum/viewtopic.php?f=4&t=46088