I agree, but, as usually, the AI counter its "lower tactical intelligence" spamming more troops than you.The fact is : Civ V AI is more ******** because in Civ V tactics are important and the AI has none . Just think of it this way : you will appear more stupid doing a Math test in college and doing 0/20 than doing a test in high school and getting 10/20 even if you have the same knowledge . Why? Because in College you're supposed to know more . Just like in Civ V the AI is supposed to know more . Its like if in Civ V the game offered us a brand new hammer to use in combat and the AI never learned how to use a hammer . We will have the hammer which will give us a huge advantage , making it way easier to beat the AI
In Civ 4 I found frustrating fighting against irrealistical and illogical unit stacks (in FFH I had to fight against a 150+ units stack just last week). In my current Civ 5 game I'm struggling in a war against England that target my cities from INSIDE it's cities (the dreaded 3-hex longbowmen reach). I won using a "fight and flee" tactic with heavy cavalry and it was VERY satisfying (much more than obliterate huge enemy stacks with cannons).
Only to add something to the much discussed Civ V combat system: I think it was designed with multiplayer in mind, so in single it seem a little flawed.