I purchased on of the force packs relatively cheaply and I am planning to buy the next big expansion because it offers the most value.

What force packs do you believe would be most useful to create well rounded fun decks?

The best three force packs (in my opinion) are also don't forget to grab EoD if you don't have it yet.

-Knowledge and Defense

-Heroes and Legends

-Escape from Hoth

I got EOD shortly after getting the base. I got the search for Skywalker, the cards were warped pretty badly so getting replacements set to me.

Those three have fun cards for all the sets?

Knowledge and defense.

Best pack ever. I use every set in that pack.

Knowledge and defense.

Best pack ever. I use every set in that pack.

Yup.

I got EOD shortly after getting the base. I got the search for Skywalker, the cards were warped pretty badly so getting replacements set to me.

Those three have fun cards for all the sets?

Yes.

Between Heroes and Legends and Knowledge and defense you'll get a super resource for each faction. I would say these are some of the most potent cards in the game. The super resources all work the same and allow you to remove a token from them when you win the force struggle. This will really show you how the meta and game has shifted to force control this cycle.

After that it's all about preference.

To expand the DS I'd say get Escape from hoth. You'll pick up a top notch Sith set! Probably the most important sith set from the Hoth cycle.

To expand LS I'd say get Join Us or Die. You'll get the new super-gun-Yoda, as well a cool tricksy Rebel character set with a resource.