I like the anthracite headliner a lot on ours but our combo is with chestnut and sienna wood trim. I do notice though that my wife keeps the sunroof shade frequently open. Are you getting the sunroof?
Have to agree that with kids black leather is wise. The black interior in my 2001 325i still looks reasonable with a 3 and a 5 year old...
I might be wrong about this but looks like MY 2014 does not have the sports package option anymore. So the only way to get sports seats and sports steering wheel (if you want them) would be the m-sport it seems.
In general the pricing structure and the package structure has changed so much for 2014 that your choice between 2013 and 2014 might also depend on what you want and do not want to have in terms of the other options.