I must assume you've grown up in the US, because thats the only place in the west where people have never watched or even heard of Saint Seiya in their youth (the english dub is atrocious, so I can't blame ya). It was a MASSIVE hit in Europe (no JoJo reference intended haha) and Latin America so I have very fond childhood memories of it, but I will try to be as impartial as possible.
Story: 7/10
Some people will tell you Saint Seyia is a very cliche 80's shounen battle anime, and for the most part that is true. But is it really a problem when this series has CREATED most of the cliches it shows? Together with Dragon Ball, SS has made popular many tropes which are widely used by modern shounen today, so you must take the cliches here with a grain of salt, kinda like visiting a museum.
The most important ones are the Underdog x Hierarchy trope (where a renowned group of powerful people are defeated by a group of protagonists which are considered to be much weaker, ex: Black Clover, Shokugeki no Souma) and the "Boss Rush" arc structure (the protagonists fight extremely powerful foes one after another in a race against time, ex: Bleach). Bleach is basically Saint Seyia with swords btw, Tite Kubo admitted SS was his biggest inspiration for Bleach.
These two tropes are essentially the plot of Saint Seiya: in order to save the goddess Athena from iminent doom, Seiya and co. will surpass their own limits time and again to defeat foes initially perceived as much more powerful than themselves. Every single arc in SS is like this, which may make it a little too simple and repetitive for modern tastes, but it uses these tropes to such great effect that chances are you'll still have a lot of fun regardless.
Art: 9/10
The SS manga was revolutionary at the time of its release for using a very delicate, almost feminine art style in a shounen manga, at a time when nearly all other shounen were testosterone filled Hokuto no Ken clones. Don't let the delicate style fool you though, the fight scenes are brutal and shows a LOT of blood! That delicate, retro art style was adapted well in the anime, and while it can seem dated at times, its still a marvel to look at, specially the awesome armor designs!
Sound: 10/10
I absolutely ADORE the soundtrack in SS. All the OPs and EDs are timeless gems that me and my friends still sing at karaoke bars to this day, so many years after finishing the series. The uplifting, exciting battle themes, as well as the melancholic ones are all beautifully orchestrated and well timed. If nothing else in SS leaves a lasting impression on you, its soundtrack most certainly will. They simply dont make soundtracks like this anymore.
Character: 3/10
This is where the series falls short, unfortunately. For reasons I dont really know, the anime lobotomized most of the protagonists, erasing key personality traits you can only find in the manga. With the exception of best boi Ikki, the main cast are all goody-two shoes with few differences between them (Athena/Saori is basically a walking plot device, barely any character in there). However, the main antagonists in the first arc, the Golden Saints, are all badasses who represent the 12 Zodiac constellations and are easily the highlight character-wise, you will certainly relate to some of them.
Enjoyment: 9/10
Watching "weak", underestimated people overcoming great odds and arrogant people getting rekt is a never-ending source of enjoyment, at least for me. If you like other anime that focus on these same feelings, then SS is a must-watch. The aura of mysticism the astrology influence gives off is very alluring and gives this series an unique feeling of epicness, AND THE ARMOR SUITS ARE SO. FREAKIN. AWESOME!
Overall: 8/10
Saint Seyia is one of the OG Shounen Templates. Combine it with DBZ and you basically have all the building blocks every modern battle shounen has been built upon, its influence was so great it even inspired other manga genres such as shoujo (Sailor Moon was heavily inspired by SS, among others). Again, if you've grown up in the west and never heard of it, you're probably american haha.
DONT GOOGLE SAINT SEYIA ENGLISH DUB. Watch the uncensored sub.
If you're a fan of shounen anime, you own it to yourself to at least watch the 1st season, the Sanctuary arc! It is one of the most iconic shounen arcs of all time, as important to the genre's identity as the Frieza arc from Dragon Ball Z (not kidding). Watch the first season and try not to burn your cosmos, I DARE YOU!
