Eubanks, as in Christopher Eubanks...the one who got destroyed by Stepanek on his comeback trail? That's my only memory of him. Blanch has a good serve but his ground game, unfortunately doesn't impress me as much right now (so hit and miss). I am hesitant to rank them ahead of Donaldson. Jared has his growing pains, mostly mental, but he is a better ballstriker.
Eubanks is 9th in the ITA rankings. He's played well over the fall and spring semesters. His serve and forehand are big weapons. It may take a while, but I like his upside. He and McDonald are the two best American collegiate players in my opinion.
Blanch is very error prone, but he can hit the ball explosively, especially on the forehand side, and his serve is one of the single best shots of all the young Americans. His recent results are encouraging. But yeah, he needs to become more consistent from the baseline and develop a more versatile game.
I would probably put Donaldson 5th in my rankings. I still like him; I'm just a little concerned about his lackluster form.