matic22
Ancient Mariner
I don't think Steve would want to continue without Nicko. It's a comfort thing. The most important relationship in a band is bassist-drummer. And Steve, when it comes to Maiden, is quite stubborn. He plays the same bass since the beginning, he has been using the same bass gear for 20+ years now, he is still on the wedges. I just think that the phase of replacing band members is over. This is the final lineup of Iron Maiden. Maybe they'll need to cut down tournig in the future, but I just don't see them getting another drummer or guitarist.I think Maiden could easily keep going if Nicko, Janick, or even Adrian quit. If they'd want to, though... that's another story.
Also, now with 5 post-reunion albums, there are quite a few songs that need 3 guitars (not harmony-wise, where Maiden has massively underachieved since 1999, but simply part splitting wise), so I think even 2 guitar lineup is a no at this point.