Quote Originally Posted by Ziyyigo-Tipyigo View Post
As far as your goal is simply "do ALL the missions!" then the only real hiccups for you will probably be the add-ons, especially the "storyline" add-ons of A Crystalline Prophecy, A Moogle Kupo d'Etat, and A Shantotto Ascension. If I remember correctly from the previous census, most players still haven't beaten those, thanks to a brutal difficulty curve and some rather broken mechanics in later challenges.
All of them are duoable, although the ACP crystal is still a challenge for certain setups.

As most things were already said by other posters, just a few notes from myself. You'll find that content has shifted towards endgame. As a result, lower levels are not quite as popular, and you'll notice this when trying to find certain gear for your levels on the auction house. Fortunately, there's very little gear that actually affects your gameplay until you reach the 50s, except for weapons, so you shouldn't worry too much about that.

Very simple endgame-related money sources include Abyssea and Dynamis. In Abyssea you'll get lots of random items from chests and random mobs that can be sold on the AH for 1~50k. Dynamis, even if farmed inefficiently at first, will still yield several hundred thousand, and can improve to about two million daily if done correctly.

If you're looking for a social LS, you're welcome to join mine. We recruited a lot of newbies recently, and you shouldn't have trouble finding people to either team up with, or higher levels to help out on things you may need. And it's also always nice to be able to quickly ask people for directions and information, which is especially useful for newer players.