Great list Justin! I have most of them, but am picking up the stray crossover books that I missed the first time around.
And if you want to go to the "next level" beyond all that, here is a list of the Infinity War ( aka: Doppleganger Special ) crossover issues:
Alpha Flight: 110, 111, 112
Avengers West Coast: 96, 97
Captain America: 408
Daredevil: 310
Deathlok: 16
Dr. Strange: 45, 46, 47
Incredible Hulk: 383
Iron Man: 294
Marc Spector Moon Knight: 41, 42
Nomad: 7
Quasar: 38, 39, 40
Silver Sable and the Wild Pack: 4, 5
Silver Surfer: 67, 68, 69
Sleepwalker: 18
Warlock and the Infinity Watch: 8, 9, 10
Infinity Crusade has some crossovers as well