I've difficulty imagining any pleasant ending for Walt, though I can't really classify him as a villain, he was starting to remind me, until just recently, of Tywin Lannister. GRRM actually made a comment after this episode about Walter White being a bigger monster than anyone in Westeros, which unless he's got an inside scoop on the remaining episodes strikes me as serious exaggeration but he's definitely in safe villain territory these days.

They have managed to avoid cliche, that's for sure.

Knock on wood, I'm optimistic about the conclusion but I've noticed that good shows/series have about a 50/50 chance of totally botching the ending. It's hard to do a tragic and/or twist ending that isn't kind of cheap most times but especially in a show like this. I do sort of wish I'd held off watching the show till it was done so I could have blazed through season 5 all at once, time to speculate on the ending is probably going to remove any real chance for shock value, though anticipation is nice too.

You're right though, I have difficulty imagining there's a majority view on most of the main characters. They've done an excellent job laying out their motivations and showing how that led inevitably to their decisions, those actions have often been surprising but not out of character which really speaks well of writers and actors. Very few weak links in the cast or plot, an occasional stretch on behavior but definitely no harsh breaks, hopefully they can keep that up for the last episodes.