It's definately too late for release, but I really hope to see a tech. advancement for the humand and vasari super-weapons that will cancel previously-fired shots that are enroute to planets you currently own.

It would naturally branch off of the super-weapon, and might be called something like "Phased Recall" or some such fancy-name... and would auto-detonate (harmlessly) any incomming superweapons to planets you now control (except the advent's culture bombs of course). 

If you'd like us to micro-manage the shots, the tech. would allow us to target a particular super-weapon and manually cancel it. 

Just a thought! It might make conquering those far-off galaxies a touch easier (if a little less exciting;))