Mass Effect 5: 10 Fan Demands We Need To See
4. New Alien Races
Despite entering an entirely new galaxy in Andromeda, most of the characters you interacted with were part of the same alien races that dominated the previous games.
Even worse, the end of the game promised that staple species of the series that weren't featured in the latest game such as the Quarians were on their way to the new galaxy too, almost guaranteeing their involvement in the sequel.
Fans have a deep connection to these aliens and their cultures, but if Bioware was going to keep the focus on them then there was no reason to change the setting to an entirely different galaxy.
Again it's another case of the series resting on its laurels, and in the future the developers need to come up with entirely new ecosystems and cultures that will wow players in the same way the original game's Citadel did back in 2007.