I don't think Iron Maiden has made a perfect 10/10 album.
Their discography is mostly 8/10 and 9/10 albums (except for the 90s where they range from 4/10 to 7/10), but no single iron Maiden album is what I would consider "perfect".
You forgot the most important one - Bruce hasn't sang a live performance for a long time because he just healed from a golf ball-sized tumor he had surgically removed from his throat.
He sounded mostly good, judging from the clips on Youtube. Most singers (including Bruce) get better the longer...
I think Bruce's voice sounds strained in some places too. Yet it also sounded strained in places on The Final Frontier, but he seemed to nail those same songs effortlessly live.
I cannot help but wonder if the guys are just mixing the vocals weird in parts because their hearing range isn't...
The best performers a know how to structure a set list that gets an audience excited during the show, while giving them a few moments of different atmosphere here and there. It's a lot like how album tracks are sequenced.
Iron Maiden has it down to a science.
I'm OK with them doing more touring next year then releasing a new album in 2015 (followed by another couple of tours).
I want a new album as bad as anyone here, but I'm relatively content as long as the band is still active. When they stop touring altogether I will be upset.
Back in 1989, when I was about 10 I got an old cassette tape without a cover of 'The Number of the Beast' from somewhere (found it in a box of other tapes my dad bought at a garage sale, I think), and I played it just to hear what kind of music it was. It was rewound so it started on Side B, so...