<< I could either go the prime way, and get the 28mm f1.8G and the 85mm f1.8G (with the 50 those would make a nice trio), or simply get the 24-85 and sort of repicate what I had with DX.>>
That's true, but you are giving up both the IQ of quality fast primes for a relatively slow 24-85mm VR. The prime lenses you talk about will give you a lightweight option, although changing them can be a bit awkward at times.
The other option is the 24-120mm f4 VR which will give you a slightly longer reach than the 24-85mm. This would be a halfway house in the extra stop area. I do know what you mean about the 24-70mm f2.8 and I am considering changing mine for the 24-120mm f4. Reports I read are that for my landscape work I would probably notice little difference.