I don't know if any of you got the chance to read the manga Pygmalio. Whilst it has many things in common with the Kid Icarus series and is possibly both the father of Kid Icarus and Zelda, there are some interesting divergences, too. Kid Icarus Uprising for instance is so much more goofy in tone, and is rarely dark or depressing, with a jovial, happy-go-lucky atmosphere. At times, it felt like the first 9 chapters were an oversimplified parody of the plot of Pygmalio. In Pygmalio, however, so many characters die, sometimes in gruesome or heartbreaking ways. Be warned if you do read the manga: it can be quite graphic in places. In the French dub of the anime, some of the violence was cut.
There are also some interesting divergences with the way they handle Medusa, too. In Pygmalio she was far more central, and is incomprehensibly powerful and devious. In KIU she was marginalised and is almost treated with contempt.