Okay, I've unlocked every ending and I'mm going to give a hint for each. If you don't want to be spoiled, stop reading. OTOH, if you're desperate for a hint , read on .
As an aside, how is 'Made' an achievement? Is it possible to play through the game and NOT be Made?
I'll rate these endings from easiest to hardest, but I'll cluster related endings together.
These endings are compatible with not killing anyone. If you don't want to kill anyone in the mob, learn to lie. Subterfuge really lessens the penalty for not executing a hit.
No Escape: Seems to be the default ending. At least, I got it more often than not. Roleplay casually, don't screw up bad enough to get a bad ending, don't do well enough to get anything better. 10 points
Riches to Rags: Use drugs, never check into rehab or quit cold turkey. The mob will toss you out at the end of the game. 25 points.
Big House: Get your heat above 100 and you'll get an extended vacation in Club Fed at game's end. Commit lots of crimes, especially involving police, mess with guards, don't pay your taxes, don't do anything whatever to bring your heat down to something manageable (say, by buying corrupt cops). 25 points.
Big Bang: Just don't pay your tribute, don't do anything to get away. You'll be pushing up the daisies before you know it. 25 points.
Got Out: Same as Big Bang, but also antagonize the family and Nelson at every opportunity. This means you'll have a bad feeling and get a chance to run after you miss the last tribute. Have subterfuge over 80 and you can get away into your own private witness protection program. 25 points.
Suburbia: Cultivate your relationship with Alex so he offers you the chance to turn informant. Take it. Run up your respect, persuade, or subterfuge up to 100 so you can record the good stuff and bust the Mob. I don't know what happens if you don't do this at the end, but I suspect being found with a wire is another way to get Big Bang. 50 points.
G-man ending: The same as Suburbia, except do well in school so you can go to college, then take one of the three college courses (pre-law, pre-med, business) and go informant at the first opportunity. Also, stay off of drugs. You'll be offered a chance to join the FBI in prison. Take it, play through the suburbia ending, sit in Mr. Hoover's seat.
I feel like an idiot about this one, TBH. I had to look it up online here to find out how to get this ending, which stumped me, but the game actually spells it out for you. In your first meeting with Alex, invite him in for coffee and ask him what he did after school. He lays out the game's requirements for joining the FBI exactly ... and I only tumbled to this much later! I wish I'd paid closer attention instead of just ignoring the paragraph and looking for status changes!
Hollywood ending: Max your subterfuge and take every opportunity to appear in a play. It may also help to marry an actress or to cultivate Freddy, the dandy who's always working with Hollywood people. Max persuade so you can pitch the movie deal to the bosses at the end. 50 points.
Senator Ending: Need 100 citizen reputation and 90+ persuade. Get into politics, stay in. Subterfuge really helps to be able to stay in politics even when called off on jobs. At the end, you're going to need some way to fight charges of your shady background: 100 legal or 100FBI/100 police rep or 7 bought police officers. I found the 100 legal the easiest way to get it done. 50 points.
Good Life: This is the toughest pacifist ending. Need at least 2 mob families (besides your own -- you don't seem to need to worry about your own) to have 80 relationship points, plus 95 persuade and 95 intimidate. Get 3 mob families above 80, you only need 1 of persuade or intimidate. Get all 4 above 80, you don't need any, although how you're going to make the Sato family happy is beyond me. I usually try for the 3 families -- make friends with the other families, don't act against their interests, give them reason to be happy with me, don't kill their people, run up a big bankroll and use 'gifts of respect' at the end to push any holdouts over the 80 point line. Persuade the last family and bring peace to the city. 100 points.
It is impossible to get these endings without killing somebody, and you're probably going to rack up quite a body count. So if you're going this way, this is a good time to get the cold-hearted killer achievement.
Bitter Boss: Have 100 relationship with 1 of Freddie, Dana, or Jimmy at game end OR have a child and bring them into the family business. Take the option to bring war to New Daria and kill the man who brought you into the business in the first place. 25 points.
Hit man: Max out your firearms skill, take every assassination contract offered. have 30 perception and 30 athletics. Buy a silenced firearm when given the option (it's about the second from the top -- it specifically says 'silencer' in the description) and a sniper rifle. Kill your rival assassin, take all the contracts you can. At the end, the option will unlock to assassinate the rival family heads. With a full set of working tools and 100 firearms you should be able to do it, becoming the most infamous organized crime killer in New Daria history. 50 points
Boss of Bosses:: The toughest ending by far.
First, you need the same as with bitter boss: 100 relationship with Freddie, Dana, or Jimmie OR a child in the mob.
Second, you need 100 respect at game end. No one gets to be boss of bosses without respect.
Third ... perhaps you've heard the Buddhist koan "if you meet the Buddha on the road, kill him?" The same applies here for Mafia bosses. If you find yourself alone in the room with the boss of a rival family, whack him.
Fourth: At games end you need to have previously killed at least 2 of the 4 bosses AND have 95 firearms AND 95 fighting. Kill three of the 4 bosses beforehand, and you only need 95 firearms OR 95 fighting. Kill all 4 before the meeting, you need nothing -- your rule of Daria will be unopposed. This ending requires exactly what it says in the final paragraph: To be coldhearted, ruthless, ambitious, and entirely without mercy.
I did this one by maxing my persuasion and citizen relationship skill, even if this meant forgiving a debt -- -10 respect I can get back in other ways. This gave me the opportunities I needed to put a max firearm skill to use. Went to the final meeting ,everyone was dead.
Interestingly enough, the only ending where you need a better gun than the free Phoenix is the hit man ending -- it requires the full set of working tools. For everything else ... there are times when a fully automatic firearm is nice, but it's never critical.
Have fun! Although I prefer the G-man or Good life endings, myself.