Admiral Tidd notes his top five challenges:
Russian and Chinese competition for influence there.
Hezbollah fundraising in Latin America.
Terrorist recruiting and attacks in the Caribbean Sea area.
Helping to defend the Panama Canal.
The Venezuela refugee problem, which is just one of the humanitarian issues that could put SOUTHCOM in motion.
As I've written repeatedly, a modularized auxiliary cruiser that I wrote about in The AFRICOM Queen could be a major asset for SOUTHCOM.
For SOUTHCOM, multiple modularized auxiliary cruisers would be useful, to focus on anti-terrorism intelligence and direct action; humanitarian response; and more conventional naval capabilities for missile and air defense and anti-ship or anti-submarine work.
Oddly the drug trade is not mentioned, but I imagine that is a major part of Hezbollah fundraising.