Celts for me is a better clansman Heavier in places, tasty guitars/bass works and the chorus(Spirit, cry….) is out of this world. F
I mostly agree with you about Senjutsu (being dark, very enjoyable and interesting records with some AOB/CW/TOS callbacks and whatnot), but for me, Death of the Celts might be the weakest track on the album and probably the only one I'd be... um, you know, if it came to that, ready to drop. I think it's very
solid song. Intro is nice, melodies are nice, verses are nice, solos aren't bad either and there's a few cool moments here and there. It just feels like a Steve Harris song that a Steve Harris Bot would write. Everything comes the way it should in a this kind of a Maiden song. Just as it should and as
you'd expect. It's very Maiden, altogether, but (for me, anyway!) not very exciting. I often feel that it doesn't really have a climax and while most, if not everything in it
is very good, it just... goes on does whatever it does quite well, but just for the sake of... doing it.
I'm not very good at this, but it just doesn't click to me. Maybe it will, eventually! Who knows.

Other than that, I think the album is very strong! Other tracks that I feel are on the weaker side have more "saving graces":
Lost in a Lost World might have some lackluster moments, but it's got a few ABSOLUTELY BRILLIANT moments and melodies too. Not to even mention the beautiful outro.
The Time Machine, as
@Kalata suggested, is bit of a "signature" Gers(/Harris) song, but that comes with... yes, trademark Gers intro, trademark Gers riffs, some trademark melodies... but hey, it's got a
great vibe and recycled as
the Maiden moment (The Edge of Darkness called and wanted it back

) in the middle might feel, IT ROCKS. Some great vocal lines, too.