I find the Egyptian/Olmec connections most intriguing.
Ahhh. S. American pyramids/ziggurats, Egyptian style headdresses, Egyptian mummies with traces of cocaine in their systems... Yes, the links are tantalizing.
But then I am of the opinion that the world was well traveled in ancient times, even on the periphery of recorded history - A study of Phoenician trade routes, to include ooparts of their design is an eye-opening experience. The same with ancient Chinese. And what goes unsaid is the likelihood that any ocean-going trade almost demands the existence of reciprocal systems (other ocean-going trade)... And that every far colony seeds the area it is in with the knowledge needed to produce and operate ocean-going vessels of their own (supposing for a moment that port-side folks are so stupid as to live alongside the great bounty of the ocean and remain incapable of exploiting that bounty...). What passes for science in this area is incredibly naive, IMHO.