You should read the Guide by Tom Brady, it's stickied. Answers a lot of questions.
Midscreen, I don't think Cage can do big combos. You need to rely on his inclose fighting speed, fast frame advantage pokes, to apply pressure.
I can only do about 30% with Pop Up (B+FK) or Axe Kick (F+BK), dash, BP, FP, F+BP, dash, BK, BK, Flip Kick or E Flip Kick if I need the damage.
However, strategically, you need to give up a bit of damage and end your combos with the nut punch - to remove your opponent's wakeup options.
So, something like: BP, FP, F+BP, dash, F+FK, Nut punch or BP, FP, F+BP, dash, BK, BK, E Nut punch.
Not really sure about his mixups. I wouldn't consider him mixup heavy.
The launcher combo is your mixup. When BP, FP is blocked (leaving you at -2 frames on block) you can:
a) perform another block string like another BP, FP or possibly throw; or
b) F+BP to launch (if they counter attack the BP, FP or try to jump out)
c) B+BK ender - its a different string ender that hits low. Works on those that block standing in fear of the F+BP launcher overhead. I think you get rewarded with a stagger state on hit so you can dash in for more pressure.
If you think they will counter attack after blocking BP, FP then your answer is F+BP to launch them. If you think they won't counter, stop the combo, and continue other pressure. Note: They can jump out for free after blocking BP, FP if you don't F+BP launch them.
