I've heard A Tout Le Monde. That was ok.
At least listen to Holy Wars... The Punishment Due. I've come to basically agree about his voice, but Holy Wars is worth a listen anyway.
As to the thread:
Nightwish is an obvious answer.
Angels Fall First is basically The Nightwish Demo Part 2. I do enjoy it on occasion—it has some good songs like Elvenpath, the title track and Lappi. But there's also some cringe-worthy material on there, like Tuomas's vocals on The Carpenter and the lyrics to Nymphomaniac Fantasia.
I'll also be controversial and say Coldplay. I know that
Parachutes is a real favorite for a lot of people, but in my opinion they really developed beyond that point. It's definitely a good album, but I like the style on their other albums better. That being said, this is a band where I think their albums are pretty close in quality.
A Head Full of Dreams is the other one that would be at the bottom of my list, but I think I'd put it slightly ahead of the debut.
I'll continue my controversial nature and also say Transatlantic. To be clear, I have no disagreements with the consensus view that All of the Above is one of their best songs, if not their very best song. But Mystery Train is definitely their worst album song, in my opinion, and My New World is their weakest epic. No question it's an enjoyable album, but compared to their other material it's my least favorite. I often listen to just All of the Above and We All Need Some Light and then turn it off.
I'm not sure I have any other answers... with a lot of bands, where I've heard they have a subpar debut, I haven't gotten it yet or don't plan to ever get it or seriously listen to it, really. I imagine I'll never own pay much attention to some of these albums, like
The Piper at the Gates of Dawn,
On the Sunday of Life, Anathema's
Serenades or Kamelot's
Eternity. I really only get the known-to-be-subpar albums of my very favorite bands, the ones I just can't get enough of.