OP - you should try 3DMark. It's a legitimate benchmark, and no, it's not biased against your Core i7-2600K.
Based on your BF4 numbers, I would say you're getting great performance, far better than a GTX 570. I think your initial posts suggested performance went down. That's clearly wrong.
But there is something keeping your GPU and CPU from 99%, and yes, in BF4, one or the other should be at 90-99% most of the time. Are you running DDR3-1333 by any chance? That could be a bottleneck. I'm also still a bit concerned about your motherboard's PCIe 2.0 x16 slot, which could also have this result.
Now, it would be easy to say "hey, you're getting great performance, just play your games," but I can understand your desire to get the most performance possible out of your new card. If it's in fact a case of a platform limitation, at least you know you're pretty close to maxing out your 1070, and using multi-sampling/DSR to push it harder is an option, as there's not much use for 100fps on a 60Hz screen anyway. And your next upgrade could be a CPU/motherboard, rather than a GPU.