I would like to preface this review by saying that I absolutely love the original series of NGE. It has aged astonishingly well, and I think it's truly timeless.
However, this film occupies a bit of a strange spot in the franchise.
About an hour is recapping the series, and the final half-hour is a "sneak-peek" at the next film in the franchise, "End of Evangelion" (which I have not seen at the time of writing).
This begs the question - if your intent is to follow the storyline of the franchise from start to finish, what point does this film play? You could watch the series and (I'm assuming) go straight to End of Evangelion and you wouldn't have missed anything. It's a bit like having a "previously on evangelion" segment, then a half-hour trailer for something you're probably going to watch afterwards anyway.
I will admit, the recapping of the series did make me view some of the themes in a different light by juxtaposing scenes I didn't connect thematically before, so it's got that going for it. But it hasn't got a lot else I'd recommend it for other than that, or for revising the story so far if you haven't seen the series in a while.
It's not bad. There's just not much reason for it existing.