Witcher 3 with W3EE
As I imagine a lot of people have done after the TV show, I've gone back to replay Witcher 3 - mostly because I always wanted to play HoS and B&W - which I never did.
Also, I have to say that W3EE could be my favorite mod of all time.
It changes, corrects and improves every... single... problem with Witcher 3.
It fixes exploration, progression, loot, combat, alchemy and so on.
Not only does it fix these things, it makes them more or less fantastic all-round.
Especially combat and alchemy.
Combat is incredibly skill-based now - and it takes hours of practice to get comfortable, but it's incredibly reward.
Alchemy, very much unlike vanilla, is meaningful and, in fact, vital for success. Given how EE changes the economy, you really have to make an effort to gather the right ingredients - and, most importantly, you have to prepare for the tougher fights, exactly like you'd expect in a Witcher game.
Witcher 3 goes from a great story with rather boring gameplay - to a game with a great story and fantastic gameplay.
It's so, so much better like this.