Katatonia - The Great Cold Distance
Their old stuff was doom metal but their latest albums have been a hybrid progressive rock/metal. Some call their new style depressive rock. Whatever the case, The Great Cold Distance is pretty good. Highlight tracks are My Twin, Deliberation, and July.
Pain of Salvation - The Perfect Element I
PoS is a rare breed of progressive metal. They incorporate many different styles of music and the vocalist has an amazing range.
Ayreon - The Human Equation / 01011001
Both albums full of a variety of musical styles and many different vocalists. Ayreon do rock operas, but more science-fiction-oriented and they definitely have a metal edge. If you don't like any sort of sci-fi related lyrics then focus more on The Human Equation which foregoes those lyrical conventions.
Riverside - Second Life Syndrome
Really good progressive rock - definitely up your alley I think.
Those are the only ones I listen to that might fit your criteria.