Steve Rogers turning up at Tony's door in the middle of the night might be a bit out of character, but it's not completely out of the realm of possibility. Stranger things have happened. Steve Rogers turning up at Tony's door with an amnesiac assassin - who may or may not have some of Tony's personally designed hardware attached where his arm should be - well that's just far too interesting to turn away, even if Tony is trying to avoid all things S.H.I.E.L.D these days.
The Man on the Bridge is at heart, a recovery story. It touches on action, romance, and mystery but is driven inexhorably forward by Barnes' recovery and Steve's grief. It's fast-paced, poignant, and endearing in turn, taking its time to show you the lives of the Avengers, as they combat trauma. If you're looking for a Winter Soldier recovery fic that you can revel in at every slow step of the way, this is the fic for you.
Spot On - this is a fic that allows characters to be imperfect, to struggle against their own moral codes, to falter and to fail, and to get back up again. It emphasizes the humanity of each Avenger, in all their differences and all their heroism.