What are commonalities in the themes of Titus Andronicus and Romeo and Juliet or Macbeth?
Titus Andronicus is without a doubt the bloodiest, most violent and gory play in Shakespeare's repertoire; it is a revenge play through and through.
If I were going to compare Titus Andronicus to either Romeo and Juliet or Macbeth, I would probably choose the latter. You could make a fairly decent argument for the development of the theme of power or ambition in both Titus and Macbeth. A strong comparison could be made between Macbeth's cunning plotting and maneuvers to gain power and Tamora's evil plotting to extract revenge upon Titus for her son's death.
On the other hand, Romeo and Juliet does have the theme of warring families and violence between the two households, which does also largely figure in Titus Andronicus. You could compare Tamora versus Titus to the Montague versus Capulet scenario in Romeo and Juliet.
All three plays share a heavily-weighted theme of death throughout, and you would be able to find many comparisons between the grisly death and fight scenes of Titus Andronicus, Macbeth, or Romeo and Juliet. Both approaches have merit and ample material for analysis.