I like the idea of these two together for a few reasons. First of all, their voice lines/interactions like this one:

Ultron: You rule the dead?

Hela: And all who will be dead.

Ultron: Then thank me later for the gift of more servants.

I like how Ultron is pretty cool with her compared to how antagonistic he is with some other characters, and he's like, "Yeah, you're getting more souls cause of me."

There's also this one:

Ultron: You are a collector of souls. Are you not Asgardian?

Hela: I suppose you could call me that, automaton.

Ultron: Then it seems you would have no use for me.

Hela: Do not sell yourself short. Your head would make an excellent trophy.

 I like the idea of Hela wanting Ultron, maybe even obsessing over him in a way due to his effectiveness/wanting him as a trophy but then potentially actually kinda developing an appreciation for him.

Hela: Quite an efficient machine, I like it.

This one, too, considering one of the things Hela wants is to expand her army of undead servants, Ultron is the perfect pick for that, and it goes back to the other interaction I talked about.

And then for Ultron, I feel like if he ever kinda developed feelings for a person, Hela feels quite fitting. I mean, Goddess of Death X Murderous AI just goes well together, don't you think?

Also, their ship name I currently have is Heltron, but I'd love to hear any other ideas for them. 

What do you guys think about this pairing?

Thoughts on Hela and Ultron?