*Just as a quick disclaimer, I'm not against the MM or normal bosses! My goal is variety for the bosses!* ^_^

In most campaigns that I've been in, the bosses were just big monsters with a bunch of HP. They were pulled straight from the monster manual. I want to veer away from that.
Just fighting *insert any boss monster* on *insert generic flatland* isn't quite as cinematic as I am going for.
In my campaign, the heroes are facing aspects of the seven cardinal sins (wrath, greed, sloth, pride, lust, envy, and gluttony). I don't think anything in the monster manual would quite cover what I'm going for. Besides, I'm trying to stay away from the MM on these important battles.

I've been throwing out ideas for such bosses. I'm rather pleased with what I came up with for Gluttony. The players will be heading through a dungeon to their initial goal on a magical levitating boat (long story behind that, it's pretty much that dungeon's puzzle). The giant fleshy beast representing Gluttony will show up and start taking huge bites out of said boat. He will continue to do so until the players manage to either fend him off long enough to reach their destination or kill him. They have precious few turns before Gluttony completely eats the boat (and probably the players as well).

But now I'm not satisfied with the other Vices. I want the same sort of drama, but I'm pulling blanks for a few of them.

So here's some questions for you if ya need a little motivation to respond. Feel free to stray from them as you like, they're just there for those like myself who have trouble forming a response out of nothing.
1) Have you ever created/encountered a "cinematic" boss in tabletop gaming? Describe the awesome.
2) Have you ever encountered a really awesome boss in a video game that fulfills my description? Gimmie the game's name and the name of the boss so I can look it up on youtube.
3) Got any suggestions for a Vice? This includes Gluttony! I'm okay with dumpin'/altering him if something better comes along.
4) How do you like to set the mood for bosses? Utter darkness save for the flickering lights of the bold adventurers? Or p'haps a little jazz and the salsa?
5) Is there something horribly wrong with this idea? If so, what is it? Am I a total NOOB for not realizing it?

As always, thanks for your help! I really appreciate your input!