I own a RED Helium Weapon and it doesn't have the dynamic range of an Alexa but I've found if you use the Truecolor RED to Alexa LUT you get a good starting point for color that gets it closer to the Alexa look (it will never be as good but its definitely an improvement). Also, you really have to expose to protect the highlights and you need to rate the camera at 1600iso. When I grade this footage, I'm always surprised about how much you can dig out of the shadows. Link to LUT below. It costs money but it was worth every penny to me. I tried to make my own RED to Alexa LUT and I could never get it as precise as this one.
I'm also finding that the resolving power of this camera is definitely a whole other beast. I've been shooting a couple of scenes at F22 on my Leica R's and you see a whole other world of detail that I've never seen before. I like deep focus so its something I appreciate about this camera. You need good lenses on this sensor because its a lot less forgiving of any flaws the lenses have.