These are the one's unown recommended to me. He mentioned you in one of them so I thought I ask.
Grisaia no Kajitsu > Great VN but VERY long. I still highly recommend it though.
- Rewrite > Made by Key so you can't go wrong with this one. Lots of intense moments and feels too. Recommended but So.Damn.Long. I doubt I'll play any other Key VNs if they are all of this length. Some entire VNs are as long as Rewrite common route lol
- Shinigami no Kiss wa wakare no Aji > Didn't really like this one. So I'll leave it at that
- Ever17: The out of Infinity > Great VN imo. Confusing as some points but it all makes so much sense in the final true route.
- Sono Hanabira series; all games, 1 to 8. Still have to play the 9th one. Short VNs with one linear route but BY FAR the cutest Yuri VN out there. Love the art and characters <3
- Cross Channel > Pretty good VN but confusing AF. If you can finish this without the use of a guide of some sort, I'll bow for you.
- G-Senjou no Maou > Really good VN. Great routes and the main guy you're playing is a total d!ckhead. I couldn't dislike a fictional character any more >_>. Ask Infamous, he'll testify for his douchbaggery.
- Hoshizora no Memoria > Pretty standard. Nice art and probably the best OST form the VNs I've played. Also, this was my very first actual full voiced VN. So even if it's not that good, it's still sort of special to me ;3
- Kono Oozora Ni Tsubasa wo Hirogete > Very enjoyable VN too. Great art and routes imo.
- Shuffle~ > Another decent VN but pretty standard. You have your Chilhood friend, loli and 2 transfer student. Pretty typical set-up x3 But hey, I thoroughly enjoyed it
- Osananajimi wa Daitouryou > Pretty meh tbh. I only liked 1 character in the entire VN and it's all pretty much "wtf" xD
- Katawa Shoujo > Really good, as I said in a previous VM