I love this show and it's underrated. The music is god tier, llisten to all the albums published on youtube, they are amazing. Art is a masterpiece, the background scenarios are really well made, the effects etc. Dub is 10/10, I mean you got Solusod Micah for Touma and Karbowski Brittney for Misaka, what else do you want? Story is great, I haven't read the light novel or graphic novel so I might be wrong but I just like it a lot, you got some fillers but it's no big deal, overall like the characters and all. I have probably rewatched about 6 times, Index I, II, III, Railgun, S, T, Movie and Accelerator. It feels like watching the MCU but with anime
The only bad points I give are for random sexual scenes that give nothing to the story, but it's anime and the producers know their audiences so I guess it can't be helped