Next PC configs: is it worth it going to gtx 1070? should I wait for Vega? RX 480 CF?

I’ve just posted a thread about problems with rendering on opencl, and besides its working now I still have some problems, specially when i try to render more detailed scenes, and there are some features that still are not suported by opencl cycles. I am going to buy a whole new computer next year (probably February), and I have already decided to go for amd ryzen (waiting for the prices to decide between 4c8t, 6c12t or 8c16t), and by now I am divided between going for gtx 1070, rx 480 8gb crossfire, or maybe wait for Vega. I also use my computer for gaming, and I have a project for the pc so that extra heating will not be a problem for the cross fire setup. I wanna know what’s your opinion on:

  1. How it is the rx 480 crossfire performance when it comes to rendering (cycles and other rendering engines if you know some)?
  2. If is the 1070 faster, is it a lot faster, or just a little bit?
  3. By knowing the vega gpu is suposed to have 8gb HBM2 and about 12,5 TFlops, when it comes to rendering, how could this reflect render time?
  4. What about DirectX 12 and Vulkan? the gtx series 10xx is known to don’t be 100% compatible to assynchronous shaders, should I consider this since I have no intetion to change my GPU on the next ~4 years?
  5. What about OpenCL support on cycles devlopment roadmap, is it expected to have full, or almost full support on next year?

I am new in the forum, and as you can see by how I do write, english is not my official language, so sorry if this thread is in incorrect section, and if is there something that hurt your eyes when you read it :smiley: