Since you already have good lenses that cover the range you use, the question isn't so much what proportion of your shots are in various focal ranges but how often you want or need the advantages of being able to go to f/2.8. Depending on what you shoot, if your main concern is low light performance, you will likely be pleasantly surprised at how well your new FF camera does even with a slowish lens. If your concern is background blur, that's another matter altogether - and you've already committed to the 135/f.2, which is pretty amazing in that department.
So if I were you, I would wait until I had the camera and then rent either or both f/2.8 lenses and see if they're an improvement over what you have for what you shoot. (And if you do that, compare the results you get with your 70-300 at 300 with the 70-200 at 200 cropped to an equivalent image; you might then decide that you really like the 70-200 you don't need to keep the 70-300.... And so on.)