Upside of having two characters?

[Veerne]

+ You can play more.
- You have to play more.

[Makado]

I did another character so I can coil to help other groups that need a person. Also desynthing is limited so you can do more with that also. Really those are the only things you are limited on at the moment, so basically while you run your alt around your making some more gil on stuff while you play it. In the future I'm sure they will have more reasons why you would want to have an alt though, so please look forward to it.