I think The Book of Souls is better than Senjutsu. The band has a bit more of a spark on it, a little more energy, and it has a great balance of light and dark, faster tracks and moodier ones. It feels like the band were having fun in the studio. Senjutsu is stuck in second gear for most of its runtime whereas TBOS often branches out in third.
That being said, Senjutsu was actually right behind it in the last album rankings I did (coming in fifth while TBOS was fourth, beaten by Powerslave (1st), Brave New World (2nd), and Somewhere in Time (3rd)). The album has been living rent-free in my head. I like every song, the quality is very consistent, the production is a step up from TBOS, and “The Parchment” has even overtaken “Empire of the Clouds” as my favorite post-reunion Maiden song. Maybe after the tour commences things will die down but I suppose actually being part of the release and not watching from afar like I did with TBOS in 2015 endeared me to it a lot more. It’s not without flaws but it has held up shockingly well and some songs have grown on me even more with time.
I will say though that it’s interesting to see how TBOS has fallen a bit in the forum’s overall estimations after Senjutsu’s release. It’s like people have started to sleep on it now. Should Maiden do another album in the future (past), I’m curious to see how this album holds up. I don’t think it’s the be-all, end-all album like some say, it’s just got a deep quality of excellent songs. TFF was overshadowed by TBOS, and TBOS is now overshadowed by SJ, and I’m curious to see if SJ too will be overshadowed by the next album Maiden put out. Will the people calling it their favorites still say that when there’s new music over the horizons? Interesting thought.