I dunno, I don't think you can really compare MR and Orchid to the rest of their albums, the first two are so drastically different.
They are great albums, and I am finally getting into Orchid. Morningrise really took me no time at all. Advent is one of their best songs and is perfectly put together. NightSilent is pretty cool, takes a few listens, as well as Nectar. BlackroseImmortal is a pretty awesome, if not slightly long song. And To Bid You Farewell is just one of the most gorgeous pieces of music I've ever heard. I play it every single time we go camping, or sit out in the backyard at night. My parents even love the song.
MAYH is so different from MR that I don't even compare the two. MAYH pretty much gave up a lot of technicality for heaviness and power and emotion. Still Life sort of combined the 2 styles, blending emotion and heaviness with technicality.
I can see why some would only really like stuff post-Morningrise, or perhaps prefer Orchid and MR to the rest of their stuff. I happen to like both styles for different reasons.