They’re both extremely excellent. The original series is a fair bit darker and more depressing, and End of Evangelion is definitely a lot more WTF than anything that happens in the rebuild movies (which isn’t a bad thing necessarily). The rebuild movies,meanwhile, have much higher production values, and the fights are generally much better–most of the gifs of Ramiel you see are from the rebuild. The characters are also a lot more mentally stable–they’re all still depressed and dealing with heavy shit, but it’s “I’m taking my meds” depression instead of “untreated spiral” depression.
Yeah, do NOT watch end of Evangelion if you’re in a bad mental headspace. The original series ending might be better for you despite the “ran out of money and cobbled together a clip show” values, since it at least has a relatively upbeat tone. EoE starts with “all the main characters are comatose or going through a mental breakdown” and it gets worse from there.