On the scale of paragon and renegade, I think the most memorable moments I have had with Mass Effect is being a Renegade with Paragon-like ideals - especially with Sole Survivor.
What I mean by this is being a renegade but try to push for paragon like outcomes - so making use of intimidation to obtain something usually obtained via persuasion, taking hard stances on those that wish to exploit and profit off unethical research, while still feeling strongly about preserving the rights of a species to exist.
Some great lines comes from both renegade actions and the contradictions.
By the time of the trilogy, I head cannon it together quite nicely as a Shepard feeling like he is always forced to make the hard choices, being someone struggling with survivor’s guilt, and internally is conflicted with the consequences of his actions and tries to do better.
This self-enforced burden has made them a bitter person, but not an irredeemable one as the personal moments help peel back the bravado and exposes someone really struggling to keep their shit together.
Tldr; Been a while since I played, but help people that are genuine and try to save civlians, get rid of elements that are rotten in society- up to you what you decided is rotten, anything cerberus is bad and have sympathy for those that suffer from being the ones used in experiments, Reaper tech research is bad and should be destroyed ( makes for a personal decision in 3), either side with or against Krogan ( have to fully commit to one for best outcome in regards to choice), know your worth and make use of your spectre status and save the council to feel smug about them being wrong
;end tldr
I will cheery pick some of my favourite examples in jumbled order
Mass Effect 1
Mass Effect 2
Mass Effect 3
Just thought of more:
Romances options: although cliche ( sole survivor )
Team mates that Shepard can probably identify with
Liara is a very broad stroke character and can be slotted into most scenarios, although she is really dedicated to Shepard considering how much she does for him.
Of course any thing can work if one puts their head to it, I just feel like this is the easiest ones off the top of my head
Thank for the extensive write-up!