My S. aurea are a pinkish brown color so that may very well be what your cousin has. For S. aurea you can pretty much follow basic mantis care, they don't need anything special done...they do fine at room temp in a container at least 3 times their body length in height with a substrate such as coco fiber to help keep humidity between 50 to 75%, mist lightly every other day (or as needed depending on the humidity where you live) and feed every 2 or 3 days. They are aggressive hunters and will eat anything that moves (they will sometimes even try to eat things that are not food!) They are prone to overeat so only feed until their abdomen becomes plump then stop and wait till the abdomen goes flat again for their next feeding (watching the abdomen to determine feed times only works while they are nymphs but you just keep the same general schedule when they become an adult.)
As for your giant Asian, the males live almost as long as females once they become adults. I have a male that has been an adult since July and he's still going strong.
My female shield mantis's eye spots became huge after being introduced to her mate. The spots varied in size a bit from day to day but pretty much stayed enlarged the rest of her life. She had absolutely no trouble seeing her prey or hunting and she would often intently watch the insects moving around in her neighbor's enclosure too. It's nothing to worry about.