Heya,
You have a 70-200 F4L IS? I would use that for portraits instead of the 85mm F1.8. Shoot at 200mm F4, and just get more distance, you'll get great compression/blur, combine with far away backdrop/outside, and they will literally be popping out of the photo. Great lens.
I would roll the 28-70 F2.8 and 70-200 F4. Work horse lenses that cover almost all your focal lengths. Maybe roll a prime for anything more specific if you truly need wider aperture than this.
Also, for indoor sports, going from F4 to F1.8, well, you will notice right away that at F1.8 you probably won't get a ton of shots. It's going to be a bit of a stretch to reach in with it, even on a crop. The F1.8 gobbles light, but also nets you a shallow depth of field. The farther away you are from the subject, the more will fit into that field, but you will still get some out of focus areas. If you want to shoot sports indoors, I think you'll get more from utilizing higher ISO. You will find the indoor sport guys throwing ISO 12,800+ no problem with their long lenses. I would just use your 70-200 F4L IS for this too, with ISO 6400 or higher, depending on how fast you want your shutter speed to be to freeze them in the light.
Very best,
Very best,