Fallout 3 and NV for story and immersion

Fallout 4 for…er…I mean building mechanic is pretty cool.

Fallout 76 is Wild Wasteland on steroids and even canonicly people outta the vault are begged to stop nuking the everloving shit outta West Virginia xD

So yeah. New Vegas best immersion and roleplay, F 76 best building (for me, it’s my own opinion - building here is less sandboxy but feels like it has a lot more meat - more pieces have usage etc.) and both for fun factor, just different flavor.