If I have no battles to fight by just being myself I would not worry about being strong. With all humility, I am a being who is happy with who I am.
I have simply no desire to take something that belong to others or to fight temptations. This is because I turn away from temptations rather than fight it. The more you fight a temptation, the stronger it gets and then you have to be stronger. It is vicious cycle in which many fail in the end.
Define yourself are you really are. If you like to be someone else, then be that person through your thoughts, words and actions. Since it is something you like, you do not need strength. However, it would become a battle if you want to be what someone else want you to be. Beware of this trap. Even God prefers that you be your true self and change when you see fit. God is not commanding you to be someone else. If God really commanded then it will be happen with or without you effort. This he will not do.
So change and became who you really want to be. This is who God is. This is how many masters like Jesus and the Buddha lived.