First off, every album has at least one song that would make the show completely worth it. Also, my least favorite albums aren't necessarily the ones I'd be the least excited about seeing performed in their entirety. Both Blaze albums would be awesome just to hear Bruce's take on the songs. Other albums have several never-before played songs that would be very cool to hear.
The Number of The Beast would honestly be an album I wouldn't be super interested in seeing live. NOTB, Run to the Hills, and Hallowed have all been played to death, I've already seen Children and Prisoner (although they are both great songs), and I have no real desire to see Gangland or Total Eclipse. Invaders and 22AA would still make it worth it, however.
A show I would be the least likely to see would have to have a set consisting of mostly overplayed songs mixed in with some of my least-liked songs overall. Something Like:
Wildest Dreams
Wrathchild
The Angel and the Gambler
Can I Play With Madness
Hooks in You
Gates of Tomorrow
Don't Look to the Eyes of a Stranger
Two Minutes to Midnight
New Frontier
Bring Your Daughter To The Slaughter
The Fallen Angel
Fear of the Dark
Iron Maiden
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Number of the Beast
Sanctuary
Running Free
Honestly, I'd still end up going to this show.