Not having both Believe and Heavenly Blue on there. They're the same damn song and both terrible.
Something with acoustic guitar would be really interesting actually. Stuff like the acoustic version of Sprinter on the 5th Live and the Christmas Lives from the Alleluia single makes me hope that it might just happen at some point.
Other than that, yes, more variety would be nice. All their previous albums have shown that it's possible so it'll be massively disappointing if they don't do it again, I'm sure Kajiura can pull it off. Their recent b-sides (especially Koibito) and songs like Kimi no Gin no Niwa seem to prove to me that she's got interesting ideas floating around still and that she's willing to create such pieces and whilst they haven't had a truly great a-side since KnGnN, I'm not too worried because of that. As per usual I'm expecting a short opening piece and then a good mix of ballads, rock and electronica style stuff as is usual, plus the possibility of something pretty unique and special.
More vocal variety would be nice, too. Keiko hasn't had much time to shine recently it feels and honestly I think she's got the most interesting voice, so I'd love to hear more vocal solos from her. Recent live performances and Koibito are giving me a very good feeling regarding Wakana though, she seems to be recovering that extra spark that made her voice stand out so much in the first place. As with Martin though, I think I'm mostly just hoping for something reassuringly decent and varied as the last year has been the first time I think they've properly lost their way a little.