I would like to see Andy Sneap to produce a Maiden album, but then again, while his produced albums sound great - they also sound alike (see: the last 3 Saxon or Accept albums produced by him). I really like the production on Firepower though.
The albums produced by him sound modern and with more power. Maybe a Martin Birch & Sneap team will be a great production (similar to the Priest team with Tom Allom & Sneap for Firepower).
On the other hand, the Maiden albums produced by Kevin Shirley are maybe not perfect - BNW and AMOLAD are top, TBOS is good and DOD/TFF have some remarks -> but what I really like is that every Maiden album has its own unique sound (different to the others) and if you listen to a random song, you easily can tell from which album is (only because of the production) - and for example, that is almost impossible to tell from Andy Sneap's production. In the end, I like and enjoy the albums produced by ''The Caveman''.