Fairchild: a strong female character, good for all around muscle
Ripclaw: gives the Avengers a counter for bladed opponents, and some philosophical wisdom
Hound: Cap deserves to have a talking car, and Hound's patriotic vehicle form and general reliance on non-lethal weaponry makes these two an ideal fit
The Ray: A DC hero who's not overwhelmingly powerful, the Avengers never really had an iconic long-term member who had inherent energy blasting powers (closest one being Captain Marvel/Photon)
Snake Eyes: I just want to see the Silent Master spar against Captain America just once, so sue me.

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