Breaking character... Personally, I agree. The Greek city states at the time were arrogant douches. The Greeks also lead the world with its philosophy and mathematics. If any culture would have magick users, it would have been the ancient Greeks. The armor for the Elves is quite flamboyant. At one time, the Greeks believed they were owed the world. The Greek gods inspired the Roman gods. If the Greeks said a certain god was no longer a god, then the Romans probably would have changed their pantheon. If you want to look at things strictly, then of course not. The armor for the greeks wasn't so flamboyant, but it was flashy with the horse haired helmets. However, in a poetic and loose sense, I feel the Elves with their arrogance and gaudy styles emulate the Greeks. If the Aldmeri Dominion were a nation in Ancient Europe, it would have to be the Greek States which is what the OP asked. If not Greece, then Macedon. If not Macedon, then another Hellenic nation.))
EDIT:
Just some quick things I forgot. Many cultures thought they were the best in the world and the most important part of it. There also have been countless arrogant civilizations that treat all others around them like trash. Chinese, Japanese, Greeks, Romans, British, Germans, Vikings, Egyptians, Babylonians etc etc etc.
There were many, much more mystical civilizations than the Greeks, that put a lot more emphasis on magic than the Greeks ever did too. In fact Greeks are probably responsible for much of the debunking of magical practices done in their cities. They were a people of art and logos(logic). Many peoples gods inspired many other peoples gods. In fact the Roman god Jupiter(or Greek Zeus) is the reason the Christian God is usually shown as an old man with a long white/grey beard. If we went back far enough we might find the spark of thought for all gods(assuming whatever god(s) whoever is reading this does not exist of course, naturally we dunno if your gods created everything to seem like it is much older than your creation myths and all that so please do not take offense! Tests of faith!). Maybe that spark WAS a god of some sort, probably the likely case for all of Nirn. Most of the gods in TES can be found worshiped in some form or another anyways. Not that they were necessarily copied.
The Greek City states...there is the first problem. Summerset Isle is a singular Nation. Secondly you pretty much contradict yourself, if the Hellenistic nations can also compare to the Aldmeri Dominion then maybe it is just a case of widespread similarities shared by many different cultures and civilizations throughout history and fiction? The Aldmeri Dominion are even less of a city state though. They are more like an Empire. (on that note is their a Thalmor leader? I don't remember if their is a king or what) The City states of Greece were distinctly different from each other in terms of culture and how they acted. There were a few common things shared by the greeks but there was also A LOT of distinction between city states. Sparta was a landlocked warrior City State with basically enslaved lower classes call Helots that did the everyday work like working the fields for instance, they lived a barebones and plain as they can get existence. They are about as far from the Altmer as you can get. The only similarity is probably the Eugenics deal with them tossing babies but they do that for different reasons than the Altmer. Athens was a Maritime Seaport with tons of emphasis on trade and the higher arts like philosophy and mathematics. Some similarity there, those traits are also shared by countless cities throughout history.
Second point. The Greeks also were not all arrogant, at least nowhere near the degree of the Altmer. Also being Greek was something different from having 'Greek' blood. In other words, if the Greeks were elves and a human was born amongst them he would be Greek, race was never a big issue back in the day, it was all where you were from not what you looked like, Race, as we know it, is a relatively new idea created by Europeans to justify the idea that Native Americans and Africans had no souls so it was okay to use them for whatever they wanted to, even stealing their land and killing them off. Btw the Chinese were historically very xenophobic towards western peoples, even other groups as well with them having stances towards the other countries around them like they were in a position of power. They still, are and a common theme, in today's China(was not always called China btw) at least, is to have a very superior attitude towards non-Chinese people. This is because their government reinforces those ideas regularly and have done so for generations. It is probably worth noting that the Chinese deserve their superior attitude in some respects because they do have a very impressive History.
Which Greek City States would you be talking about specifically for your case btw? I am curious.
Your third point The Greeks hardly wore flamboyant armor. http://www.hellenic-art.com/armour/bodyarmour.htm. Notice all the flamboyant armors are followed by Royal and such. The armor you are thinking of was mostly for show and was not used in battle unless a leader had a taste for the flamboyant and a penchant for death. The point of the Plume that sometimes appeared on their helmets was to signify rank so on the battlefield low rank and file soldiers could identify officers. Most Greek soldiers wore a variety of armor types(mostly plain) and plain helmets. Besides elven armor looks much more like ceremonial platemail to me. Odd that it is classes as light armor. Moonstone must be really light! But that aside armor has very little to do with culture and is entirely superficial. http://www.china-cart.com/bookpic/20117/20117162710.jpg for instance though it is hardly ancient chinese. Looks more like elven armor than any of the Greek armors I have seen. But again that is pointless.
Fourth Point. The Chinese also had a huge impact on philosophy and mathematics as well as many other cultural achievements that could easily rival what the Greeks contributed to history, they did for Asia what the Greeks did for Europe basically and then some, come to think of it so did the various Indian civilizations. To add to that the Phoenicians also contributed to the alphabets of many cultures including the one we are typing in now. The Chinese religious practices also were taken and integrated into various other cultures as well because people always like to copy from the smart guys. In fact you could say the Chinese themselves copied from a society in India to gather a newer form of Religion called Buddhism which was later adapted into various different forms in China, Japan, Korea, Thailand, etc etc..
So yup, Chinese and Greeks share this much at least. Both had their religions copied, somewhat superior attitude towards outsiders and massive cultural achievements that changed the world around them for many years. The Altmer did that too! So did the Nords(human counterpoint to the Altmer, very hostile to all non-nords, created the human presences on Tamriel and freed them from their elven overlords, the Imperials copied from the Altmer and Nordic pantheon and combined them)...
My point is that whatever you pick inevitably has characteristics shared by many cultures.
If the Aldmeri Dominion HAD to be a nation from ancient Europe, I would say they are the Minoans. Just because I can pick out many similarities that make them fit with them. Just like you can do with any civilization if you look hard enough. In the end this exercise is an effort in futility and as soon as you think one of the TES cultures is like a real world culture you will start to lose the idea of what that culture is because you will start drawing parallels that are not there but seem to be.