Nice list. I'd go with Oberto or Ratliff to begin, since big men are a big need for the Celtics with Perk not playing most of the year, and KG and JO's injury history. Plus big men tend to go more quickly than guards.
More importantly, if Danny's plan is to fill out the rest of the roster with vet min guys, the Cs are not winning a championship. Period.
It is very important for the Celtics to have quality bench players, who can play 25+ minutes a night, because the bench players will get a lot of minutes during the year so as to keep the wear and tear off the big three.