It wouldn't surprise me if any of the top four teams in the East made the finals. Detroit and Boston are relying on players who were injured this year, and the stress of the playoffs can exacerbate that, unfortunately. I'd still consider them the heavy favorites, though.
I would be more surprised if someone made it out of the West besides the Spurs and Thunder. They're just deeper and nastier than the next rung down teams to me (Nuggets, Rockets, Wolves). The Lakers might have been in that second group before all of their injuries.
Something I saw on Reddit that surprised me - Kevin Durant quietly played 78 games this year, 36.4 MPG.