A lot of this depends on how deep your pockets are. The 3 lenses you mentioned are all excellent and would make a great addition to any kit.
Building your kit around what you have now and where you want to be is what we all agonize over.
You have, I think, three fantastic lenses for your 7D, of the three choices you highlighted to add to your kit the one in my opinion that would make the most difference would be the 85/1.2. This brings the ability to do something new at an aperature that you don't have and will make a huge difference to your shooting style and shooting options. But only if as you say you want to shoot what you listed in the beginning, but if you have a yearning to shoot insects, than you make a different choice.
If you are keeping the 7D, keep those 3 lenses, or maybe think about moving the 50/1.8 on one day, but not soon.
Good luck with it.