Somberlain
Arcane

-SoTN DOESN'T have copy pasted enemies everywhere. Hell SotN has literally places where you have like 1 unique monster that isn't used anywhere else that dies instantly. I think you are confusing it with later games.
I meant stuff like that really, really long corridor in the Marble Gallery that has just Diplocephaluses and later Stone Roses over and over again, or between Clock Tower and Castle Keep there's this large room where all the enemies are just Sword Lords. And having multiple identical enemies in the same room isn't a problem in itself, it's just that in Symphony these enemies tend to be placed so far from one another that you just move forward, kill the enemy and then move to the next, one by one. In Classicvanias and later Igavanias you are often forced to fight groups, often with a mix of different enemies, which makes it more interesting and difficult.
-Backtracing is issue with later vania games after Down of Sorrow as you get shops and trading proper which were existing previously but they were worthless since you could easily find better gear. AND unlike those two games souls mechanics wasn't that much expanded so you didn't need to grind and do something with those souls thus you didn't need to backtrack.
Sorry but I don't really understand what you are trying to say here. What I'm saying is that Symphony has too much backtracking and probably more than any other game for a few reasons. First of all, there could be slightly more teleport rooms. Second, there should be teleport rooms next to the inverted castle portal and the Master Librarian. In this way, you could use a library card to warp to the librarian and then immediately jump to the teleport room closest to your destination. Symphony has the biggest castle in the series and non-veterans will constantly have to run between locked doors and rooms they haven't gotten past yet to figure out how to advance. Better teleport mechanics would really reduce the boring running through same rooms over and over again.
Order of Ecclesia does this the best. It has a Baldur's Gate style world map and a village that acts as a central hub. You can warp there with Town Cards that act like the Library Cards in Symphony. Then you can immediately exit the town and go to the world map location of your choice. Last, all the bigger locations have a teleporter next to the entrance. OoE has less tedious back and forth running than other Igavanias and it's still just as long.
-def level isn't high for any vania game after super4. Even SotN isn't that hard.
Again, I'm not sure what exactly you are saying here? Symphony is too easy, probably the easiest game in the series. Harmony of Dissonance and Aria of Sorrow get really easy too in the end, if you explore the whole castle. It wasn't until the Nintendo DS games that Igavanias got enough challenge.
Also, I would argue that Rondo of Blood and Dracula X are harder than Super Castlevania 4. I'm not entirely sure about Bloodlines, since it's been long since I played it.
-platforming in castelvania ? wut. I mean sure it is 2D game with platforms but that doesn't mean they are platformers. In fact DS ones vania games with added gimmick platform based stylus were worse than just lack of platforming in SotN
Are you saying that Classicvanias weren't platformers?

Most of the later Igavanias don't have much of it either but Portrait of Ruin and Order of Ecclesia have the most. For example, in Tymeo Mountains, Tristis Pass and the Clock Tower. In OoE you even have an entire (optional) dungeon that is pure platforming.
SotN is special because it is the first of chain of new vania games and rightfully is named the best new vania game but Dawn of Sorrow isn't really that much behind. Soundtrack wise i'd say DoS and SotN are about equal as both have some amazing tracks. Later PoR drops quality a bit and introduces way more backtracking that rest of the games in series and since it is a sequel to DoS it isn't interesting plot wise.
Yes, Symphony is special since it revamped the entire series. That obviously also means that they hadn't yet fully figured out how to perfect the Metroidvania formula since it was their first attempt. It is only natural that later games made improvements on it, even if they weren't as good in some ways due to the lack of production values and scope.
But I'm not trying to hate on Symphony here, I love the game. I just think it's unfortunate that everyone knows Symphony and everyone thinks it's a classic but a lot fewer people have played other Metroidvanias, both inside and outside the series. So they think that Symphony is the apex of the genre even though many games have made improvements on it later.
My second point is that games like Order of Ecclesia prove that Igarashi still has what it takes and isn't just some washed up old guy who made some great stuff 20 years ago and has no talent left.