I stand by my statement that UTF was the last time they were consistent.
Since then, they've put out their worst stuff, some of their best stuff, and a lot of mediocre tunes that would never have existed on earlier albums. Moving towards more vocal driven music may have played a part in this.
Adam & Eve and Paradox Hotel are seen as some of their weakest of the era, especially A&E, but I think that one is good, it's just it's an album surrounded by even greater albums, and might be the weakest of the first 10 albums, but still stronger than a lot of recent material.
I like Paradox Hotel, I don't think it's their best or top 3, but I consider it one of their better albums. It's a TFK album with a reversed track order, (thus PARADOX Hotel) and I like that idea. I just think there are a few strange songs on there, and Monsters & Men is a sleeper epic for most who've heard it, including myself. It's a slight departure from where they were at the time, but the music was still interesting and captivating unlike some of the more recent material (which is the last 4 albums to me) which overall sounds like the band (or Rione) going through the motions and/or stretching out ideas from a dried up well.
TSONE was the band going back to their upbeat symphonic prog style, and I think it's one of their best albums. All killer no filler, just the meat of their usual double albums. Love Is The Only Answer is one of my favorite epic of theirs.
As I alluded to, the last four albums (five, if you include Manifesto of an Alchemist) are all hit or miss for me. Each album has some good stuff, and a lot of stuff that isn't very memorable to me. Now of course, this is TFK we're talking about. It took me years to "get" the band and their music, but I find that the better material from their later albums isn't as enjoyable as their older stuff that is more middle of the road, let alone their best pre-2008.
As for the change in keyboardists, I don't know if Bodin had something to do with any riffs or heaviness in the band. I do know that the change did not have as much to do with how good the last few albums are. The last album Tomas appeared on (Desolation Rose) is my least favorite TFK album, and I find Banks of Eden to not be as good as what came before either. I actually like the more recent stuff a bit more that those last two Bodin TFK albums. The band feels a little sterile on BoE and DR, whereas the more recent stuff feels more alive, like the old TFK I just think they're still in a transitional phase with the new members. Hopefully the next album will be their return to form type album.