Straight off, I have to say there is nothing inherently wrong in principle IMO in having one unit per hex and having a paper rock scissors combat system. In multiplayer it might turn out to be excellent. However, in basing Civ 5 combat on Panzer General, history was ignored. The AI in Panzer General and all the other titles that followed it was completely unable to handle offensive operations. In defence it didn't have to do much, the player mostly had to figure out how to solve the puzzles that the map setup involved. In a dynamic game like Civ 5, there is no way that the AI will be able to handle paper rock scissors - unless Firaxis magically cracks the AI code that eluded the General series. So the AI is crippled offensively. That means it will lose lose lose even if it spams units. The standard CIV stacking system avoided this problem because defensive and offensive units would mix, not giving a smart human player the opportunity to take apart the AI. Hopefully I'll be proved wrong.