Just wondering if anyone wants to share upgrade advice that they've noticed. Good example: Samurai have a GG bonus; upgrading them keeps it and is of benefit for your modern infantry units. Caravels have extra sight (2) promotion. Destroyers have extra sight (3). It will stack. Bad(?) example: Artillery are required to set up before firing. If upgraded to rocket artillery, the set up requirement is kept so you end up with a rocket artillery unit that requires setting up. However, maybe that is worth it if your artillery unit is quite powerful. Another bad(?) one possibly: Ranged units like archers etc will eventually be upgradeable to standard infantry units. This leaves any -ranged- combat promotions rather useless. Thoughts?