Re places to visit
After the colonial zone, the Must places to see are the Botanical Gardens, the Zoo and the Aquarium. I am sure that you can finde people there in Boca Chica more than happy to escort you wherever you wish to go and you will certainly enjoy them all.
Safety is not an issue, unless you try walking around under the bridges in the dead of night!
Heck, Boca Chica just starts to get hot at midnight!....
HB