Let's face it, Maiden are lazy to an extend on the fact that they could have 2-3 spots on the setlist where they could switch songs around from night to night. If Metallica can do it, Maiden sure could.
The Paschendale\Dance Of Death switch that was done on the begining of the 2010 US tour was the most refreshing thing they've done in a while. I was so pissed too when they stopped alternating those 2 songs. That give fans that do multiple nights a surprise to expect every night.
Songs that would have pretty much the same lenght and they could have a generic backdrop that fits both songs. And even the backdrop issue is not really one, they could have backdrops for both songs on a specific spot if they really wanted.
So that current set could be something like this (I did it for 5 spots there which is pretty much pushing it for Maiden to do but come on, that's definatelly doable. And imagine the possibility of sets that that would make
2. Can I Play With Madness or Wrathchild
3. The Prisoner
4. 2 Minutes To Midnight or Killers
5. Afraid To Shoot Strangers or Infinite Dreams
6. The Trooper
7. The Number Of The Beast
8. Phantom Of The Opera
9. Run To The Hills
10. Wasted Years or Still Life
11. Seventh Son Of A Seventh Son
12. The Clairvoyant
13. Fear Of The Dark
14. Iron Maiden
15. Aces High
16. The Evil That Men Do
17. Running Free or Hallowed Be Thy Name
you see I'm not always saying they never do wrong