Warthur
The first Neal Morse Band album was a deliberate exercise in Neal Morse shifting gear from his usual approach to making albums. Don't have a plan, don't have anything pre-prepared, just go into the studio as a group and cook everything up collaboratively.
To my mind, it was a major success - and clearly enough people thought the same to make it worth giving the Neal Morse Band idea another shot. This time, however, things seem to have shifted a little, with Neal taking on a bit more of a "band leader" role - seeing how it's his name on the cover and all - whilst not totally abandoning the collaborative approach of the group.
In particular, The Similitude of a Dream is based on a concept decided by Neal (it's an adaptation of The Pilgrim's Progress), with lyrics all written by Neal, and in a format which was ultimately decided by Neal. (Reportedly, he and Mike Portnoy had a disagreement over whether it should be a 1CD or 2CD release - Mike favoured a shorter album to prevent the concept from wearing thin - and Neal eventually got his way.)
That isn't to say this is a reversion to the approach of Neal's solo albums, or the time he spent as leader of Spock's Beard - an era when he'd write more or less all the music and lyrics and everyone else was there to execute his vision and did only minimal songwriting of their own. Once again, the credit for the music goes to all the band members - and once again, you can hear that, with more nods to pastoral-era Genesis and Pink Floyd (for example) than is typical for Neal's usual writing approach, plus some even wilder stylistic curveballs (there's bits of Draw the Line which seem almost nu-metal influenced, in terms of having a hard, funky instrumental basis which you could imagine a nu-metal vocalist rapping over at points). All this is the the sort of thing which also felt novel and interesting on The Grand Experiment, and so seem likely to be the contribution of other band members.
The shift here, then, seems to be that Neal has taken on the responsibility for providing the broader structure and concept, whilst the band as a whole take that framework and put the meat on the bones. It's a change which makes a lot of sense; The Grand Experiment was successful, of course, but it's the sort of thing which can only really be truly novel once. Coming into the studio with at least an outlined concept to hand is the sort of thing which focuses the mind, and having that sort of focus saves the album from being a mere rehash of what came before.
Using The Pilgrim's Progress as a concept also makes a lot of sense in terms of Neal's wider career; although Neal seems to be more open than he was back in the 2000s to be involved in projects producing music which is secular, or at least not overtly and explicitly Christian, he does like to involve his religion in his art. One of the things which is genuinely good about the prog albums in his solo career is that he doesn't just restrict himself to the same very limited set of themes which more conventional Christian Rock artists tend to rag on about over and over again. He's aware that Christianity has a rich cultural history behind it, and he'll use that to do concept albums based on obscure parts of the Bible, or Church history, or - in this case - Christian allegorical fiction.
In addition, the whole "weird allegorical journey" thing which The Pilgrim's Progress is based on is, of course, exactly the sort of thing which has been the substance of a bunch of great prog concept albums of the past - The Lamb Lies Down On Broadway by Genesis is exactly that concept, in particular. (For that matter, so's Spock's Beard's Snow...) Basing the album on the structure of the original story means that John Bunyan is, in effect, an additional collaborator - because in his lyrics Neal is interpreting Bunyan's characters and plot, rather than coming up with his own story from whole cloth.
The end result is something which is both different from what Neal Morse would have come up with adapting The Pilgrim's Progress all by himself and then just handing down the finished compositions to the band, and different from what the Neal Morse Band would have come up with just wandering into the studio with no fixed plan for a second time. As such, despite all the retro-prog influences on it, the album still seems fresh in the context of Neal's prog discography, and helps to continue the revitalisation of that side of his output which the Neal Morse Band represents.