I still love the ending. Basically you get to Loghain and you find out he's been fighting for the same cause as you, just with completely different methods. Maybe he took power opportunistically, but he still wanted to protect Ferelden. You beat him in the final battle and he submits to your judgement. Riordan is pragmatic and suggests you make him a Gray Warden, in order to take the hit from the Arch Fiend and die in your place. Loghain is even cool with it because it means he will be remembered as a hero who saved the kingdom and not a usurper. It seemed like a good idea.
But then Alistair loses his shit. He hates Loghain and believes completely in the nobility of the wardens. At that point in the game I totally saw Alistair as my bro. He had stuck by me through all the crap and been a faithful and loyal companion, suffering endless abuse and tanking through all the toughest mobs. I felt like I owed him a debt and respected his opinion. So when he declared, "Being a Gray Warden is an honor, not a punishment! I will not call this man my brother!" I realized, shit, he was right. I was really moved by this. I hadn't looked at it that way before but I realized Alistair was completely correct. The game persuaded me to change my mind. Loghain fucked Alistair hard and put him through a ton of shit. Maybe it wasn't the pragmatic thing to do, but a bro is a bro, so I cut that fucker's head off.
I just thought that was a pretty cool way to end the game, and even though it doesn't really matter in the sequels or the game's official ending, it's been pretty rare for any game to actually get me that involved in the characters and the story enough to give a shit like that. So way to go Bioware. Since then of course they've become pozzed up the ass, and every character sucks harder than the next, but I'll always remember killing Loghain out of loyalty and spite.