This is an excellent observation to make, as the act of renaming is very prominent and important in the Bible as God seems to rename various individuals as he uses them and makes them part of his plan and actors in his narrative. The key to the renaming is the meaning of the name which such individuals are given. For example, Abraham means "father of a multitude" and Israel means "to struggle." In a sense, what we see happening in the Bible is God powerfully breaking in to people's lives and setting them on a different course that is part of God's divine plan for them. The act of renaming is therefore very symbolic of this as there is a change of identity.
The meaning of the new names they are gives are also important to either indicate how God is going to use them, as in the name of Abraham, or to highlight the time when God very clearly met with that person, as in the case with Jacob/Israel. There is perhaps an aspect of foreshadowing with Israel, as the wrestling match between God and Jacob could stand as a metaphor for the relationship between God and his chosen people over the coming years.