As far as I've seen all siege units have progresses by adding 40-50% power with each upgrade. This is not true to Rocket Artillery, with its whooping 100% power upgrade from Artillery (28->60). When you add to that, that they have +200% combat bonus vs cities just like older siege units, it gets really ridiculous. Even very strong cities can be reduced so zero health with couple of RAs. Plus they are ultra mobile, compared to older siege units. Personally, I think they are too good, for their class. Sure Stealth Bombers or Bazookas are better on open terrain. But against cities, RA is like one tech level further then it should be. I think they would be better balanced with +100% bonus vs cities. Do you agree?