Inhabit the character as little or as much as you wish.
The Mass Effect trilogy straddled a very fine line, offering players a customizable character that they could project themselves on to, while also at the same time ensuring that that character was his or her own person, with his or her own character, past, and identity.
A major reason for them being able to pull this off was their offering default appearances and names for Commander Shepard, male and female. And, going into Mass Effect Andromeda, it seems as though that will continue to be true- speaking on Twitter, Bioware’s Mac Walters confirmed that Ryder, who will be the protagonist for Andromeda, will have a default name that will be revealed at some point in the future- and that just like in the Mass Effect trilogy.
So- once again, you will be able to define the character as much or as little as you want. I think that’s just the way that Mass Effect players would want it.