Hello,
From what I understand from your post, you are inquiring how to balance between a self-insert MC (The Warden Commander from DA:O) and a pre-set MC (Commander Shepard from the ME trilogy), is that correct?
There have been numerous threads discussing this topic, or related to this topic, that I encourage you to read through.
What do you want in a protagonist?
Protagonists are unrelatable
How would people feel about well defined protagonists?
Freedom to select MC’s personality
This is one of those topics that people have a lot of different opinions on since there’s no universal - at least, among forum goers - “right way” to go about this. Some people like more defined MC’s and some people like blank slate MCs to allow for self inserts. It depends on the reader.
Obviously, some of it will depend on how well you execute the MC while walking this tightrope which may influence the player’s feelings while they read your story. On the other hand, some people won’t like coffee no matter how much cream, sugar, milk, chocolate, etc. you add into a cup of coffee. The coffee, in this case, being your story and how you decide to walk this particular tightrope.
Best of luck.