Imo, EoE should be considered part of the original show because it's what they intended to do before running out of money. Some of the previews in the last few episodes never aired and only show up in EoE, for example, and uhh spoilers but some things in EoE can be understood to occur concurrently with eps 25/26. If I had to choose, though, I would agree that EoE is definitely better than the show's ending.

The Rebuild movies are still kind of interesting but not as good. The first movie is basically identical to the show with very, very minor detail changes (Misato is a higher rank and knows about Adam), and the second is a further slight departure, but the third and fourth go completely fucking off the rails. I'd say to watch them if you enjoyed the original show + EoE.