One of the most classic Final Fantasy games right now in terms of content is XI. I recommend it, as there is a new expansion coming out this March with 2 new jobs (Geomancer and Rune Fencer). Blue Mage is already in the game and it has a ton of good magic spells! Plus White Mage has a ton of spells, Black Mage does too, Red Mage is more about solo enhancing magic, Summoner has a good wealth of summon Avatars to have and obtain (even Odin, but I'd recommend Fenrir when you are able to get him).
Right now I'm hooked on XIV as I cannot wait for A Realm Reborn to come out. We will get Arcanist first and then later Summoner. The graphics are awesome 
However, I've been writing a fanfiction for years and it is actually a Pokemon and Final Fantasy mix. Trainers can have jobs and they fight alongside their Pokemon in battles against other trainers. There are also classic Final Fantasy monsters in the story. I'm using a lot of elements from FFXI and FFXIV in the story. I have one Trainer who is a Dragoon and rides a Charizard, and her sister is a Monk who owns a Blaziken (they are both military leaders). The main character has my real name and he's wanting to become a Warrior, and his Pokemon is a Growlithe (lol). But meh, I haven't had time to write that story in years.
