For good anime music with a severe nostalgia dose, I tend to go back to the Slayers season 2 opening:
https://www.youtube.com/watch?v=yJAIygMVRuc
Also, since it hasn’t been posted yet, I maintain that Cruel Angel’s Thesis is possibly the best anime opening ever:
https://www.youtube.com/watch?v=t-QSmNReDyI
Dragon Maid op is nice, but I want to also point out the ED, which is in rare category of anime endings that I like enough to listen basically every time.
Gundam SEED has some spicy musics. How many times did that reverb piano come in and you say NOOOOOO COME ON DON’T END THERE.
And then you start the next episode immediately. Oh hey, TMR!
Bringing in TMR into this is almost cheating…almost.
https://www.youtube.com/watch?v=IR7CvJZ01co
This series is varying degrees of hot garbage, but the first opening is choice with the music and the animation style. 
Second one from E7 because that show had excellent music
I love the song, but it’s been always super in the nose that they were gunning for the Cruel Angel Thesis sound, specially since by that point they are not even trying to pretend that E7 is not essentially Eva Light.
Besides, the second opener is Da Bombu.
Way to make me feel old Scott. I think Mahoromatic was the first anime I watched as it came out on fansubs I downloaded on Kazaa.
Wow, you’re young.
Right?
I watched Escaflowne retail subs as they came out one per month in the US and got VHS tapes mailed to me for fansubs.
I am pretty young, just turned thirty, but Mahoromatic was the first fansubs I downloaded mostly because I didn’t get my own PC until I got my first job when I was sixteen. I had the parents who thought “all your games make the computer slow” and downloading anything let “the hackers” in. Before that I was sending money orders to some guy in New Jersey to get subbed anime on VHS.
I make no claims that E7 some paragon of amazing anime. It was what it was. A perfectly adequate mech anime with a bit of a pie in the sky ending. It’s music, however, is sublime. Hell how about:
https://www.youtube.com/watch?v=NrXWOR18yaI
Ok so it takes about a minute before it actually becomes a song. It wasn’t an opener or a closer though. It was played during the anime itself. And like “don’t lose your way” from Kill la Kill it was excellent at it’s job.
Well played. Sir.
https://www.youtube.com/watch?v=Sv7RCNEhyhM
I’m not even close to done yet. I fucking own this thread.
This is the only original Galaxy Angel opener still on YouTube (that isn’t from a game) and that’s a shame. They were all at least this good.