This is too difficult so I'll just pick one of my favorite bands for which I have a well formed opinion, Opeth.
Favorite song... I say this with a ton of hesitation but probably The Moor. I'll spare you the 1.5 min faded in intro and start you off where things get going. It, like most Opeth songs, are about the length of a children's cartoon episode.
The moor, Serenity Painted Death, Bleak, The Drapery Falls, Blackwater Park, Deliverance, Master's Apprentices, and a less heavy but a top tier classic, A Fair Judgemen... or To Bid You Farewell. It is so hard to pick a favorite. Their best songs run a deep playlist.
Least Favorite song: The Grand Conjuration
Why: this song represents the band fighting like hell for that 'fuck you' money. It was an appeal to RoadRunner Records. It was overproduced garbage and it was exactly what RoadRunner Records wanted. I firmly believe Mikael wanted at least the chorus of that song to be what ultimately became the ending to track "Porcelain Heart," on the subsequent record. Very rhythmically and melodically similar underlying chord movement (one chord is a half step higher, it is otherwise identical), but a way more sophisticated idea overall.
I think Akerfeldt knew he wanted to shift the band to less metal and more 70s prog. I think he knew the only path would be betraying his fans. I think he knew the only way that wouldnt end the band outright is if he could get that fuck you money first.
I respect Akerfeldt for doing what he wanted rather than what his fans wanted. I understand getting there required a degree of selling out. But grand conjuration will persist as an actual deal with the devil he made to get what he wanted. That song represents more artistic sacrifice to me than anything else they put out.
At the end of the day, Opeth never sacrificed who their fans wanted them to be while performing live, and that matters more than any new material they put out then, now, or in the future.
Opeth is fucking awesome.
Fun Opeth Fact: original band member Peter Lindgren left the band after over a decade due to burnout in 2007. He is now the CEO of fucking Candy Crush. He is the backup vocals and guitars on every song mentioned in this post with the exception of Porcelain Heart.