I don't personally complain about the vocals - there are other things I could complain about regarding the production - but in this particular case I don't see the contradiction.
With Bruce, I kinda tend to think he is losing this quality as he ages (and I personally welcome that, I always felt the already-busy sound of Maiden is better complemented by a more down-to-earth vocalist like Blaze, whom Bruce starts to remind me ... but maybe it's the material itself, which is becoming more and more X-Factor-ish) and putting him further back in the mix might threaten with "drowning" him in the sound.
I don't think it happens or that's really a concern, but I get the reasoning behind those complaints.
I also don't have a problem with the vocals in the album or think it's something to worry about - I don't want every song to be with high vocals. Even Priest's latest album doesn't have that many songs with high vocals from Rob (or that many fast songs, btw).
Bruce
said he uses more of his lower register in this album and I think that's intentional and to support the mood of the songs (like in the pre-chorus of LIALW, for example). I'm sure he'll use it for his solo album too. And it's not like there aren't any high vocals in the album - title track, Stratego, LIALW ... as for the other songs:
TWOTW - the vocals are fine.
DOFP, Darkest Hour (it's a ballad), Hell On Earth - the vocals are high enough.
The Time Machine - the vocals here are aslo high and perfect.
DOTC - high vocals won't fit here and the song doesn't need such a feature.
The Parchment - song without a (potentially high) chorus.
And to make a comparison - the high vocals in TBOS album were in half of the song in it.
I can't agree with you that Maiden's busy sound need a vocalsit like Blaze, Bruce is really perfect for the band and their vision. And his voice never reminded me of Blaze's voice, even nowadays. The material in the last few albums is
X-Factor-ish, yes (especially in
Senjutsu), but not the vocals.