Wall-o-text incomming!
DO A BARREL ROLL!
Im still sticking to my "guns" here and saying that from my perspective it looks like (and feels like) Greek mythology (although now that you pointed out that the forerunners created "Eden" I do understand where your coming from). Id like to point out that not only did the Forerunners create "Eden"...the ~entire~ reason for the Human V. Covenant War was because the High Counsel (the ugly aliens in robes) realized that the humans were descendants of the Forerunners and that if anyone got wind of this information it would overthrow their hierarchy...and their POWAH in shambles. Just like in Greek mythology where some men were demigods who were imbued with the power to do great things humans were given that same ability.
Let me quote a excerpt from the great Wikipedia:
"Returning to Circe’s island, they were advised by her ( Tiresias ) on the remaining stages of the journey. They skirted the land of the Sirens, passed between the six-headed monster Scylla and the whirlpool Charybdis, and landed on the island of Thrinacia. There, Odysseus’ men ignored the warnings of Tiresias and Circe, and hunted down the sacred cattle of the sun god Helios. This sacrilege was punished by a shipwreck in which all but Odysseus drowned. He was washed ashore on the island of Calypso, where she compelled him to remain as her lover for seven years before he escaped".
"Having listened with rapt attention to his story, the Phaeacians, who are skilled mariners, agree to help Odysseus get home. They deliver him at night, while he is fast asleep, to a hidden harbor on Ithaca. He finds his way to the hut of one of his own former slaves, the swineherd Eumaeus. Athena disguises Odysseus as a wandering beggar in order to learn how things stand in his household".
I know that Bungie wont be creating another game in the near future...I seen they signed on with Activision or some shit. I've seen on some site i was searching one late night that if Bungie ~were~ to do another game in the future MC would crash land on a lost Forerunner planet (If you played through on legendary you got to look at it...). Sound familiar? it should!

Coming down the home stretch i wanna finish off saying that after Athena (a Forerunner?) gave Odysseus (MC?) his disguise as the old beggar, the beggar sets up the challenge to string up the long bow and shoot it through all the rings, finally revealing himself to the suitors (Covenant), and fight them out of his home and off of his wife (...Cortana or Earth?). I know that the Elites are sided with the humans now and that their alliance with the Covenant ended but I don't think that means the war with them is entirely over just yet...so it could be that the Phaeacians, who were "skilled mariners", pick up John several years later and bring him home...to "Finish The Fight!"
I didn't know most of those games you named off, lol Aaaand that's why Science Fiction's better! TYRANNOSAURUS WITH LASER BEAMS?! YAAAaaaa!! *Peter Griffin style*

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Those who do evil to others - the killers, the rapists, psychos, sadists - you will come to know me well. Frank Castle is dead. Call me... The Punisher.