Something that many players think is hard about an MMO is to find the class which suits them. For example in EverQuest I personally went from a Rogue then to a Cleric later on. It's a big change of pace to go from damage dealing and stealth class to paying a healer that has the primary objective of keeping people alive instead of doing damage and stabbing stuff!
As for EverQuest II you have 24 classes to choose from. Not exactly easy to make up your mind and it would take awhile to test all of them, especially if you want to discover what each class can do at higher levels. Fortunately, you won't have to do this, thanks to the extensive "choosing a class in EQII" guide which SOE released very recently.
Please note that not all classes are available to all races initially. Races are chosen by alignment (good, neutral, or evil) and appropriate classes are then available to choose from, depending on the race alignment. For example, you cannot choose to be a Dark Elf ranger or a Froglok defiler during the character creation process. There are some exceptions to this rule when a character betrays their home city, but not during the initial character creation. Classes are based on four main archetypal roles: the fighter, the mage, the priest, and the scout.
Do you have any classes to recommend in EverQuest II? How about if you want to be part of the "holy trinity" at damage dealing or healing for instance? Or if you want to be the master at crowd control? With 24 classes, there has to be certain classes that excel over the rest.