Brian Wilks, but more because of implementation than his character alone. Troubles in Greyditch/finding him a home feels like an early midgame quest that gets forced upon you almost right out the vault. With all the scattered locations, the perk/skill checks in his dialog you likely haven't had time to invest in, and the ants can easily be a problem for low level characters. The fact that he spawns in one of the areas you're very likely to go to right away (Either for Moria or the subway entrance) feels scummy when you probably have to put the quests on hold for a little bit if you want to get the most out of it. Your character doesn't know places like Rivet City or Paradise Falls exists yet, he ends up being stuck in Greyditch for a while anyway. All the while you have to hear about how you're neglecting him on the radio. He's super annoying through no direct fault of his character (unless you find the child NPCs annoying by default, then the annoyances stack)

I know this will likely be an unpopular opinion so please forgive me, but I've never liked Piper. Something about her in-your-face-ness bugs me every playthrough.

Honestly, I'm probably just jealous.

Even though I played 4 a ton, I really don't remember many of the characters - they all were so one sided and shallow.

So you're right... Pick someone from 4 and you won't be that far off. Except Nick Valentine or Father - they were pretty good. Kellogg might have been good, but a couple minutes of backstory isn't enough to save the character.

I never cared for Tennypenny.

I’m not a fan of characters doing things purely “for the evilz” and he’s such a shallow evil rich guy with a backstory that creates a bunch of unneeded questions.