Legend is correct for mid level players, atties are pretty powerful, as they dont require econ tricks. Each civ has its easy points, and tougher ones.
norse, hard econ to manage, two type of villies, no real counter units, (example, if you have units like Peltasts out, you want to physically micro them to attack archer units by hand, with a unit like Raiding cavalry, or Throwing Axement, it isnt as important, you can win battles by letting them just hit the nearest target) Norse dont require thought on making favor. NOrse dont need to rebuild drop off points, movable cart. Only two military buildings to keep track of, longhouse, fort. No need to micro villies to build buildings, have infantry will build And fast too. NOrse military upgrades upgrade fort units too, easier to keep track of/less decision making, unlike eggy, where you might invest in rax upgrades, then not be able to afford a midgol upgrade...Greeks, hard econ to manage, but for other reasons. COunter units require micro, favor must be factored (how many, when do you assign villies to temple, putting even one more villie on temple early slows your econ slightly) Greeks have the most buildings to manage. (rax, stable, archery, fortress - no other civ has 4 buildings) More buildings means you need to think ahead. invest in barracks and realize you need cavalry? You might be in trouble.
Eggy. Well they are defensive, and defensive is easier to use than offensive. Why? Unlike Loki, you dont need to micro attacking units, make buildings AND move back accross the map to make villies, assign them, move carts close to wood, etc) Eggy have 3 military buildings to keep track off, but are very flexible, well rounded military once you get to heroic. Need more wood, just move your Pharoah (again, flexibility) Eggy do require more things to keep track of, pharoah, priest early on. Attie, big debate here. A very good player at AOTS, Olympus MU finally pointed out why atties arent as easy as people think. Villies are easy to use, but more susceptable to being attacked, and moving 3 villies away from raiders is like 9 of regular units. Their villies are slow, dangerous to have them far away from buildings, military. Also, attie units in classical are counter units, meaning they do great vs the units they counter, but suck vs other units (again, this is argued a LOT). Turmas require you to micro them manually to attack their archers if you want to be good with them. In attie vs attie battle, if you micro and he doesnt, you will ALWAYS win. Atties have moderate amount of buildings to keep track of, no factor in gaining favor, even easier than norse. Obviously no drop off points makes them very easy to use early on, and for lower rated players.
Overall, Attie are probably the easiest to learn with, followed by norse. Eggy and Greek, hmm, most would say Greeks are hardest to learn. Eggy are fairly straightforward. Zeus, imo, is the hardest god to play (complexity). He is flexible, but the flexibility also requires forethought.
If you are still reading this, thanks.