I was inclined to rate it 7-ish but I feel like it deserves an 8 or 9 for being able to somewhat pull off such an ambitious concept of a story. I went in blind possessing only the knowledge of the theme being Time Travel and was expecting a crossover of Thriller and Sci-fi like Erased, but it turned out to be Fantasy/Sci-fi instead, which I assumed was going to flop hard after the first 2 episodes. But the truth is it ain't half bad.
Characters: 9/10
ML is a level-headed and realistic character instead of the usual edgelords. FL is also extremely cute and likeable in a very realistic way. The first episode had me thinking that it was going to be another trashy anime packed with fanservice. I'm glad I was wrong. There are also no moments in the story where I find myself wishing that the characters possess the IQ of at least an average person, which rarely happens trust me. I gave it a 9 instead of a 10 because I feel the motive of the antagonist lacking and not fleshed out enough.
Story: 8/10
Let's face it, there is not a single time travel fiction that doesn't fall victim to paradoxes. Summertime Render is no exception naturally, but it's good enough in the sense that it isn't riddled with obvious flaws and deus ex machina. The flow of the story is logical enough in its universe. The fact that they managed to pull it off even with fantasy thrown in the mix is in itself praiseworthy. The pacing is great and consistent.
Animation: 10/10
Feast for the eyes. Absolutely beautiful and character design is on point.
Sound: 8/10
OPs and EDs are great, but a little lacking in between. Not enough to complain about though.
I wouldn't call it a must-watch but it's no doubt top class entertainment. A solid 8/10 from me. It's a shame that not a lot of people have heard of it.