I would think that there is much to indicate that the play does focus on dislike more than love. The backdrop is the intense rivalry between the Capulets and Montagues. Not a single scene transpires in the play without this level of antagonism operating in the backdrop, constantly posing a vigil on individuals and one that is present in the interactions of the characters. At the same time, much violence in terms of slayings and death happen as a result of this familial dislike. I might also suggest that there is little to indicate that Romeo or Juliet experience a great deal of true love between one another. They seem to be instantly attracted and are infatuated with one another, but do not seem to exhibit elements that would constitute a stable and consistent sense of "love."
You can certainly argue that the play is more about hate than love. After all, it is hate that drives much of the action in the play.
Of course, Romeo and Juliet's love for each other is a big part of the play and it gives some of the more famous moments, like the balcony scene.
Even so, it wouldn't be much of a story without hate. It is the hatred between the two families that makes them have to hide their love. It's the hatred that makes Friar Lawrence have to devise his crazy plan that ends up getting Romeo and Juliet killed. Finally, it's talk of hatred and its consequences that ends the play.
So, you can argue that the play is about hate because it really explores the consequences of hate more than it explores love.
The play Romeo and Juliet has two themes that rely on one another to create an understanding of the dynamics of relationships--the power of love and hate. One could easily conceive that hatred is the stronger theme when looking at the tragic end that befalls the star crossed lovers. The ongoing feud between the two lover’s families results in the youths making a decision that causes both families to loose their loved one to death. While Romeo’s love for Juliet prevents him from initially entering into a fight with Tybalt, he later becomes enraged after the death of his friend, Mercutio. Hatred and anger lead to the need for revenge. The path of hatred pre-set by the two feuding families guides the lovers to their own demise.