Would Captain America and Black Widow make a good couple?

i think they are both very broken people from the various shit they have lived through, so i think they would be good for each other, and that is what we have gotten to see between them as friends, i truly think they needed that friendship more than sex, as both of them had a lot of baggage around love and such stuff.

Possibly.
I think the things that unite them are loss and grief. Which are hardly the best basis for a relationship. But it gives them a start.

Yes because she's so obvi a domina, and he's so obvi a subbie.