I picked up Star Wars: Age of Rebellion a while back and I am going to be starting a new session soon with some friends that are keen. However I noticed a lack of force users and smugglers in the rebellion and I know some of my players would like to play those types.

Is getting the other two books worth it in terms of the classes, races, worlds and other things or is it very much of the same that comes in Age of Rebellion?

Are there any other books that really help a first play session besides the starter kits?

There's links to the career/spec trees fan made. Let them peek and I think that'll answer your question.

I think it is worth it, not only for the specs (which could be cheaper obtained by buying the according spec source book, like "Fly Casual" for smugglers, but it is worth it as well for the themed gear, background, adversaries, adventure hooks, etc

The core books offer about 50% the same content, but the other 50% are a good deal different and focus on the specific setting of each.

Still, I would recommend that each player buys a different core rulebook, for rules referencing one is absolutely adequate, but for reading and sometimes looking stuff up having all 3 within the group and one the table is very handy. Plus Fly Casual, which is quite the essential splatbook if the group gets even slightly involved with space ships.

Is your group composed of Star Wars fans? If so, what kind of question is that?

It's worth it. Not only will you get more player options, but also more NPCs, vehicles, ships, and gear, as well as staging tips planets, and such.

The big difference to note aside from Duty/Obligation/Morality is that EotE and AoR handle sabers a little differently than FaD. AoR/EotE treat them as exotic artifacts and heirlooms, rarely found items of imminence power that the player will not be able to ever truly use with any proficiency (saber are powerful, but no saber talents, trees, or even skill is available). FaD of course takes the side that many player will want one and will be able to learn to use it properly, and nerfs the saber a tad. It can be upgraded to be just as, if not more powerful than a AoR/EotE saber with some time money and effort, but out of the gate it's not as powerful, though the fact the player can actually use it properly and not just swing it around like a second grader with a stick makes up for this.

So as you make you campaign it's usually a good idea to look at what that players want to do and pick the saber method that matches that. If you have a player that wants to be a "Jedi" then the FaD method is probably what you want. If not, then the EotE/AoR method is probably more your speed.

I agree.

In my opinion, for a really well rounded Star Wars Role Playing (SW RPG) campaign you should have all three books.

I really like the obligation rules from EotE as a way to customize player duties and liabilities. They're great for handling and driving player motivated sub-plots.

There are similarities for the careers in both EotE and AoR but (as a player) I still like having access to all of the careers located in both EotE and AoR for non force users. I've put together three characters so far and was really happy that I could tailor the character to specific careers. (Two of the characters are siblings who grew up doing similar things, but I found one career worked really well out of AoR for the first character, but felt the EotE version was more appropriate for the second sibling).

For force users, I find FnD indispensable. If your group isn't going to have ANY force users, then you may be able to skip this book for now. As for Force Users, the Morality rules are a great idea.

And FnD has unique and cool rules for lightsabers. I would not introduce lightsabers until you have FnD.

All three books include some of the same basic races, but each book also contains unique species. Having the added options for players may be welcome.

Yeah, each rule book contains different space ships. That alone was worth it for our group (and me a humble player).