Any questline that involves you searching for someone is difficult to get right. If the player doesn't feel a connection with the person they're looking for, there's little to stop them getting distracted.
For example: I had a little side quest earlier where a member of my settlement had been kidnapped by raiders. I got right on it, suited up in my power armor and rescued the heck out of my armor shopkeeper. I cared about that guy, so I did the quest.
Oblivion's MQ also worked better because it didn't try and force a backstory onto your character. FO4 is just "You're a heterosexual, middle-class, American with a baby called Shaun. Go.". How am I supposed to identify with my character when I'm none of those things?
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I'll have to disagree with you guys on the Ghouls. FO3 ghouls were so goofy and stupid. FO4's really give me the spooks.
Having fun fighting Super Mutants though. They're really tough. The suicide bomber versions are the worst, since they use a mini nuke and just run at you.
Fought a Mirelurk Queen earlier too. That was...not fun.
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As for the humour aspect, I kind of get what you mean. I felt the same when Skyrim came out, like it was missing something that I loved about Oblivion.
Saying that though, I have found a crashed spaceship, complete with alien. My character welcomed him to the wasteland in the traditional fashion

"If more of us valued food and cheer and song above hoarded gold, it would be a merrier world."
"...a quotation is a handy thing to have about, saving one the trouble of thinking for oneself, always a laborious business."