From your post and the fact that you did not emphasise on a particular field, I gather you're trying to further strengthen your prime lens line up. Your list of candidates within the said budget is understandable. 85L is a specialised lens and needless to say, it does well what it's intended for. As nice as 85L may be, I don't think spending your whole budget on one prime lens is going to do you good as a photographer.
If you do not need that extra oomph that 85L has over its alternatives, I'd suggest sticking to the plan to get multiple lenses. Over time, you will have opportunities to upgrade each of those lenses if you need to.
Back to your system, you have both FF and APS-C bodies. You can take advantage of the 1.6X crop factor and leave the 135 out for the time being if you go for a 85 lens. By the same token, why don't you consider 28 f/1.8 and 85 f/1.8 (or Sigma's new 85)? With the FF and APS-C, you'll have the following FOVs:
28, 45, 85, 136 - all at f/1.8
Wouldn't that be close to the four lens line up you have in mind (but only with two lenses)?