The nice thing about Mass Effect 2 and 3 is that Renegade often means harsh pragmatism and "big picture" thinking, not just being an asshole for no reason. Going all the way renegade is still hard without being a jerk, but it's easy to end up with a balance of renegade and paragon while not making truly bad decisions.

In the first game it does usually mean being an asshole for no reason, so that one's hard to play other than nearly-pure paragon. Except for hanging up on the council every time you talk to them—they give you plenty of reasons, and you should definitely always do that.

[EDIT] typo fix

I guess so; I found myself doing a few Renegade actions in ME2 and ME3 despite being pretty much pure Paragon player - harsh pragmatism, as you say. But in 1, it's harder (more black/white).

And the Council, yes - they worked hard to make me regret saving them in ME1...

There's a few spots where a Renegade action just seems like the right thing to do. I'm particularly thinking of the helicopter repairs while recruiting Garrus in ME2, and the final response to Kai Leng in ME3.

Bad guy is always more fun, Tie Fighter is better than X-wing, but being annoying griefer guy is not.

Except in WWII games. During the early days of WWIIonline there were a few people who took playing german units a little too seriously and were quietly asked, told, to stop. I was a member of a german squad that rarely participated in mass offensives specifically to avoid confrontations with die-hard "recreationists".

I've usually found the opposite to be true. But perhaps because I like more of a challenge. In most cases I've seen, playing as the 'bad guy' was easier, because you could basically do whatever you want with minimal consequences. Completing objectives as the bad guy was simple. In contrast, being the 'good guy' often involved playing with your hands tied by certain restrictions, which often forces you to think more about how to complete your objectives without breaking the rules. I even tend to impose rules not explicitly indicated by the game, just because it seems like it would fit the character's ethos and makes for more of a challenging play.

Example: Mirror's Edge. You could get your way out of most (all?) situations without killing anyone. It was pretty challenging but also rewarding. I tried to play this style, managed to get to ~2/3 of the game before my (then pretty weak) computer gave out. Had only to restart a part of a level once, because I accidentally kicked a policeman off the building.

The original Deus Ex game was similar. I remember getting about 2/3 of the way through without killing anyone. I remember being backed into a corner and finally making a kill, then "screw it, I'm killing everyone". That was an awesome game though, so many different ways to accomplish the mission. At one point you become locked into a single path though, which always bothered me - IE, you can't choose to continue helping the bad guys at a certain point, you always end up fighting against them.

Yep, I've been playing Shadow Tactics, which is modeled after the older Commandos series. One difference if the addition of unfriendly civilians, who will report you to the nearest guards if they see you. Nothing in the game indicates that you shouldn't kill them, but they do show up separately in the after-mission report. A couple levels have achievements for not killing civilians, but they have achievements for a lot of obscure restrictions as well. Yet most of the civilians are just innocent people going about their lives who happen to live in the area that has become interesting to the plot. So, I can't help but want to avoid involving them in any way. I started out avoiding them even noticing my presence, and even when I was unable to find a way to avoid a particular civilian, I've used nonlethal methods to temporarily knock them out while I do my business in their sight area. I guess this kind of thing adds to my sense of accomplishment. Of course it doesn't stop me from occasionally murdering a helpless but inconvenient innocent out of frustration, before reloading a quicksave.

Then there's open world games like Fallout that allow you to steal everything not nailed down in entire settlements, gaining more currency and supplies than you can likely ever use. It feels cheap to me and I find it more interesting and challenging to obtain what I need more ethically.

This is interesting. What was the problem with "recreationists", specifically? Are you saying there were players that styled themselves as actual Nazis?

Yes. Thier out-of-game websites were extreem. They were playing as SS units, something definitly not part of the game. There were no user-created assets in-game, but they would still pose in swastica formations seen by other players. It was all shut down rather quickly.

(Fyi, WWIIOL was probably the first mmorpg in a persistant game space. This was new territory.)

There should be more degrees of morality, most games make you choose "kill this person" vs "let them live", but there's more than murder to be a villainous character.

I play the game as if it were actually me in the main role.

I usually end up being some form of neutral character.