We will be staying at the Westin in Horton Plaza in late March. Is Balboa Park a reasonable and walk from Horton Plaza, or should we drive? How about the Navy Pier and cruise ship terminal? They appear to be only a few blocks from Horton Plaza, but is it a safe walk? I am assuming it is, since I have been reading that most of downtown SD is, for the most part, safe. One last thing--our son wants to see Petco Park, even though there won't be any games yet when we're in SD. Can you see anything from the outside of the park, or would it be a waste of time to walk over there?