Why would you compare Beckham with Franklin? Franklin has had one great season but he's not a legend of the game. He's not even the best in the league currently.
Which is better is not proved by which is more popular worldwide. AFL has been professional since 1897 now, which is only 111 years. Sports that spread worldwide were the ones that were spread through British colonisation years ago. AFL never had a chance because by the time it had built up as Australia's most popular sport (it wasn't always massive here, used to just be the winter sport as opposed to cricket, the national sport), it was too late to really spread overseas, entire nations don't just say 'wow, that's a great game you've got there, let's start playing it properly.' For a sport to go pro, it has to have a massive following, and in the current world's state, that would take a very long time, with lots of development and expansion.
As it stands, the AFL is still focusing on taking over New South Wales and Queensland from rugby, and has more important things to worry about than trying to go overseas. As powerful as it is on an Australian scale, it has nowhere near enough resources to really push the game abroad. Especially when you look at cricket, which has been pushed into markets such as the US for years but has gotten nowhere.
Complexity is neither good nor bad, it depends on whether the complexity actually leads somewhere positive. Sometimes it just confuses people and doesn't improve the sport. In the case of AFL, its extra dimensions all add to the excitement of the game.
And skater, what does more than one goal mean? The aim of every sport I know of is to win the game, to score the most points. In AFL it's quite the same. You want to kick goals, and win the game.
