Agree with Karma being underrated.
In regards to underrated songs, I don't think you can state any Still Life songs. If you asked me what my favourite SL song was I couldn't tell you. I'll say The Moor, then think of GLament's beautiful acoustic sections, the feeling I get from MVertigo, onto the awesomeness that is SPDeath and finally one of the most epic finishers ever recorded, WCluster. I simply see SL is a brilliant album in its entirety and I'm sure others do too. If you ask me what my favourite Opeth song is the answer will probably be When or Advent, without giving SL songs a second thought due to my inability to choose my favourite song off the album. So in conclusion, I think SL songs are highly rated even though people don't state it directly.