Brave New World is the most un-Maiden sounding record they have done. It sounds great, but it is also an album very much of its time. Funny thing is that it still isn't played to a metronome, so you get this clean, big production - with songs that speed up like they do live. The Wicker Man is ridiculous when the drums come in...
They could continue on this path they have done, but the most interesting thing would be for them to change things up - a reverb and delay heavy record, for example. Let Adrian write some cool new short song, Janick can do an epic with his awesome melodies and harmonies together with Steve and so on.
Bruce take on it, as I mentioned - was that he wanted the fans to wonder what they would have done next when they decided to disband.