11. Make It So We Left The Milky Way Directly Because Of Shepard
One of the most enticing and all-round most plausible fan theories doing the rounds pre-launch, was that the Andromeda Initiative was assembled as a direct response to Shepard's various comments on the Reaper invasion. Although said knowledge was mostly kept hush-hush, it's not too big a stretch to assume that a relative of someone in the know got wind of what could be coming and set about putting plans in motion, just as a "What if?".
Now, if you've uncovered all of the optional Alec Ryder memory fragments, you'll know the game DOES go very close to saying this was the case, showing Garrus' father, Castis, informing Papa Ryder of the Reaper discovery, but it happens after the billionaire Jien Garson already has the Initiative underway.
We have a mysterious benefactor (most likely The Illusive Man) helping get funds together since the beginning too, but actually starting the Andromeda Initiative BECAUSE of Shepard's warnings and findings would've provided a much more engaging motive and purpose to the expedition overall.
Leaving under the motives of fear and survival rather than as a glorified science project immediately gives the Initiative a far more defined reason to exist, as in the game, the only real drive to succeed comes from the weight of the expedition i.e. Making 634 years in cryo and 2.5 million lightyears of distance matter.
By cementing the thought process that the Reapers were coming and the Milky Way could then be wiped out, it makes every new step and foothold made in Andromeda count towards a more meaningful end goal - especially seeing as the very last thing Ryder says before the credits roll is, "We did it".