No matter which Dem makes it into office, we'll have tons of acrimony - just look at the Obama years. This idea that one of these candidates is going to magically bring the Repubs into the land of reasonable discourse is just nonsense. Pete, Beto, Biden, etc. who keep saying flowery stuff about unity and continue to have no policy plans are just going to give us more of the same hope without change that we've had for decades.
On a side note, I've been coming to the realization that it doesn't matter all that much who the President is. What we really need is a complete overhaul of Congress, especially the Senate. I don't know how realistic it is for the Dems to take control of both houses, but I'd MUCH rather have control of Congress and let Trump remain in office.