I still have not upgraded my midi controller keyboard. I just never got around to it. I was highly interested in the M-Audio Pro Series keyboards but I think I have found a newer board that comes with a little more value in my opinion.
This is the Arturia Keylab Essential MK3 and it is absolutely beautiful. It has a sleek design and comes loaded with all the features you need to get creative right away. I love the color and the way the controls are laid out. I also believe the chord and scale modes are a nice addition to play with.
The last and probably most important feature with this keyboard is the Analog Lab software that it comes with. I have heard nothing but good things about its sound library and because it is also designed by Arturia, it has tight integration with this keyboard. If I am to upgrade in the near future, this product is currently at the top of my list.