First, I'm not going to be putting up a review of Exist Archive. To be completely honest, I put it down around New Years' and didn't play it again for weeks. I tried to pick it back up yesterday and today and just couldn't. I'm dropping it, even though I'm only a few battles away from beating the game (for one of the endings, anyway).
Why? To put it as simple as possible, the game feels like a chore to me. I'm not having fun. The story and characters aren't that interesting to me. Normally I'd soldier on despite that, but to top it off, there are long loading screens and in order to truly 'finish' the game (and I like to really 'finish' any game I put a review up for), I'd need to play it through at least one more time in New Game+. I just can't do it. I just went ahead and watched the endings on youtube instead to give myself some closure. Since I'm just a hobbyist and not a paid professional reviewer, I have the luxury of just not finishing or reviewing a game if I'm not having fun anymore.
So for those of you who aren't allergic to Japanese high school boy protagonist settings and the like, I advise you to get it on PS4 at least so that the loading screens are less painful than the Vita version. It won't live up to Valkyrie Profile but maybe you'll have fun with it anyway if you like the characters.