I have some trouble with the emitter / emission materials.
If I use a “normal” emission material and change the intensity of the emitter material - nothing happen. Not lighter / not darker.
If I use a physical based material and want to at some emission -> Rhino crashes.
With Cycles on board it is a big jump but there are also new expectations of the users because Cycles is able to replace Maxwell or V-Ray or… in some or maybe most cases. And based on this thought the emission function is very important to get advanced outputs.
New render engine - Ne possible comparisons to the other systems
By the way I really like the new render engine (now not just in the viewport!)
I actual use the last beta build (macOS)