I agree with the arguments brought up in this topic that going 'extreme' either way is bad. I don't care much for either full-paragon or full-renegade. I played a lot of my first few runs through ME2 as a paragon, straight up. Then I went more Renegade on things that didn't seem like they were obviously horrible and thoroughly enjoyed the experienced far more than I did with the pure paragon runs. I think its important however to maintain a balance. Going too far into either side, imo, hurts the experience.
Unfortunately this was made difficult for me, personally, in ME2 due to the paragon/renegade system countering each other out. It was difficult to really play a 'mixed' moral role, imo, since a lot of dialogue options tied to you having a high amount of one or the other. Though these were minor things in all honesty. Personally I hated not being able to select a certain dialogue due to not having enough of one score. Or not being able to say the paragon/renegade choice because my bar was too heavily in the other. Thankfully I can just use the gibbed editor to give myself max paragon and renegade scores so I don't have to worry about those things and just enjoy playing Shepard however I want. ME3 doesn't have this issue due to the reputation system and I love it for that.
A see a lot of players dissing the scars and while I understand their reasons, personally I've grown to love them. Since I played paragon for most of my ME2 runs in the beginning I never really got into the scars. I even used the med bay to fix the scarring, because it made Shep more attractive. Aren't I vain? Though now, after my renegade experiences? I'm really loving the red scars. It makes my Shep feel more like a battle-worn soldier and reminds me of the whole "Shepard died and isn't even completely human anymore" part of the story. Though I don't really like that your paragon score hides the scars. The whole nonsense about Shepard's attitude and feelings somehow effecting the cybernetic glow... I thought it was just silly, honestly. I would had preferred it if they made it so you HAD to get the med-bay treatment to fix the scar tissue. Though to compensate reducing the cost requirement would had been nice.
In fact to avoid this "paragon curing scars" nonsense I mod my game to ensure that renegade scars remain at full capacity regardless of Shep's current alignment. Unless I plan to play a paragon, of course.
Seeing what some people say about some of the renegade actions though really shows the power of personal perspective. I mentioned already that I have disagreements with some of the renegade actions but some of the things I've seen mentioned in the thread that have been linked to 'sociopath behavior' I disagree with. Even if I don't like the option myself or go that route there is almost always some justification for the renegade responses. Almost.
My biggest complaint about renegade, other than some of the more 'obvious' parts, comes down to the ambiguity of the text selection. What you see is not always what you get. Though this holds true for all responses in the game I feel that this effects renegade responses the most. I've had to reload the game at times because the lines that came from the renegade response were so much harsher than what the initial text represented. Though I suspect this may work both ways - there are some renegade lines I've completely avoided saying (mostly to Thane) because the represented text looked too harsh.
Someone mentioned earlier in the topic about how Dues Ex Human Revolution handled this and I agree. I felt the way that game handled dialogue choice was far superior and left less to the imagination. When you selected dialogue to say, it said it. I dislike Mass Effect's method of trying to summarize the entire spoken dialogue into one brief line of text that may or may not be an accurate portrayal of the represented dialogue. I remember several times awkwardly ending up in an unintended flirt because of this. Till this day I'm still cautious around certain characters to avoid risk of sending unintended 'mixed signals' - lol.