I love Neon Genesis Evangelion, and I'm here to explain why.
It's funny, because I've never watched a mech show before. The first time I watched it, I was 17 and went in blind, being promised a fun shonen anime by a friend- so take it from personal experience, do NOT mistake this for a fun shonen anime. Not that it isn't ever fun, but everything that happens in it feels visceral and builds up characters in some weird, unique formation of trauma.
In fact, I'd call Neon Genesis Evangelion a show that explores trauma- or rather, how an individual responds to the trauma presented to them. Whether you're a neglectful father who lost his wife, a teenage boy battling loneliness and inferiority, a Major dealing with the past and raising kids that aren't hers... all that and more is explored through heavy character interactions, subtilities and unsettling imagery.
Note that this show is the very definition of "rewatchable." It may even be a necessity to catch all the details handed out. When I was 17, I actually didn't care for this show. I didn't hate it, but I didn't understand what was going on. I watched it again on a whim when I was 24, last year, after my best friend sang high praises about it. This time it hit me like a truck. Maybe being older and wiser helps. Maybe I just paid a little more attention. Maybe this time I saw Shinji's dissociation, Misato's alcoholism, Asuka's demand for attention, and I dug my nails into the flesh only to find something unspeakably human.
Animation buffs, detailed character-enjoyers, and trauma survivors alike- I encourage you to give this show a chance, or even two. There's plenty to enjoy. :)