I did not expect those songs to perform so low, relatively speaking! I know the sound you're talking about not liking on Gravity's Union, but I can't say that's ever really bothered me, personally. And NWFT to me is just all killer all the way through, so that's one of those "tastes" moments. I do think it's cool that Gravemakers and Gunslingers did so well. That's not a song I ever really think of except when I'm listening to that album, but it's really good.
I don't have a solid idea of the right way to approach Opeth here, so I'm just going to send two songs I like from the era that is more likely to perform well, I guess.