Easy (or easiest) Level ups

[Aqua]

Well, you could always go back to Pride Rock, since it is a higher level world at that point and you can gain experience points faster, or if you do not feel comfortable fighting in Lion form there is Agrabah or Halloween Town. However, if you are talking about the water clones that you have to destroy within a time limit, have you tried using the reaction commands? When you approach some of them, you will see the option of hitting triangle (as of now, I cannot remember the exact name of the command, somebody else may know) and it will allow you to swing it around and destroy a few others nearby. I have found it to be the quickest way to deal with the water clones.