Standard modern physical shaders and lights
I have used Maya for since version 5 and im teaching Maya at college last 10 years.
For the long years, standard renderer changed 2 times(Maya software, mentalray, and now arnold), and many third party renderer can use on Maya nowadays.
mentalray was good integration, it works well on standard shader(phong, blinn) without any additional knowledge because it still rely on classical algorithm, except occasion using GI or physical shader.(mia, mil..etc)
now rendering algorithm get more developed and maya standard shader can not handle with it because those have not almost changed for 20 years.
So i think its time to make modern STANDARD shader for physical renderer. Autodesk said, "we have decided to create an open rendering ecosystem for our products where different renderers, including both mental ray and Arnold can compete equally." but still we are forced to use arnold's shader when we want to render for "more realistic image"
# ofcourse, we still can use maya shader with arnold, but arnold does not support bump map on maya shader. Only at this point, i have no choice except arnold's specific shader on teaching, Also because maya shader doesn't have physical correctness.
My big concern is, when our students graduate and get job at production company, they need to study about shader again if they have to use renderer other than arnold
If we have "standard" modern shader, we can render image only with knowledge of the shader on any renderer.And renderer specific parameter should be placed on the shader as additional parameter(maybe this is work for renderer plugins).
Not only shaders, lights should be updated. Almost modern shader support IBL, skydome, shaped light, but those can not be setup without renderer expansion.