Hell, if there's one property out of the ones already announced that's probably big enough to deserve the SDCC spotlight, it's probably either IT or Stranger Things, and since the latter's already been announced...
Halloween is big, but I almost feel like it's too familiar to need the SDCC slot. Maybe that'll be the big "come over" August announcement. Have big title cards like "40 years ago, HE came...Now, at Halloween Horror Nights, He's back again!"