I am a staunch believer in Vattic's faithful. It's usually up to date pretty quickly and is basically just a high res version of vanilla. I confess I have not checked on it's current status/ correction, link https://minecraft.curseforge.com/projects/faithful-32x/files/2618816
Seems legit. The only problem I have ever had with this pack is finding one that is truly current. Some say they are current revision but then once loaded has missing textures. This one was updated three days ago, so I am hoping it's cool.
I've been using Chromo Hills for some years now and I love it. It's a not very surprising mix of vanilla-inspired textures with a medieval focus and a flavor of cartoonish textures. Like many texture packs, it does take a little bit of time to get used to it as you'll have to relearn your ability to distinguish between blocks (especially in your inventory). I love the way the world looks though. It's also fully updated to 1.13.
I second the vote for Faithful, I don't tend to like the textures that go too far either way to realism or the plain daft so I find it's a nice middle ground. But then I'm also the weird one that quite likes vanilla textures so...
Zomb, does Optifine help with the texture packs at all?