I'm feeling pretty similar to the OP. Played and loved FO4 since it came out, but the replay value for me isn't what it is for previous titles. I always (and still do) have games of FO3 and NV going even though I've seen just about everything in those games. I'm trying to figure out why FO4 isn't the same for me. I don't think it comes down to one single mechanic, I really don't know yet what my issue is (not helpful, I know). Haven't played the Vault DLC and not really looking forward to Nuka World, I'm having more fun learning how to mod.