Although I don't follow NFL very much, I do watch a few "world" sports. My adopted teams are basically ones that I have seen live while abroad (Canterbury Crusaders from NZ in Rugby), or at least been to their city (Sydney Swans in Aussie Rules). Because I have never been to India, I picked the Kolkata Knight Riders in IPL Cricket because they had a cool, menacing logo (which they have since changed).
Interestingly, the Swans and the Knight Riders won their respective championships this past season. On the risk of sounding like a hipster, I was in before the glory.
If I am close enough to potentially attend a game every year or two, that would also be a deciding factor. In MLS I like the Vancouver Whitecaps because I'm only an hour-long flight away to catch a game (I saw two last season). Some people don't like the idea of using proximity as a guide, but it does make a difference to me because I can actually go there on a whim to see a game. Obviously, this doesn't matter as much if you're as far away as Sweden.
Would picking an Eastern team be easier to watch in Sweden? With three hours difference between the East and West in North America, it could mean the difference between watching a few games live or having to record them.