Sometimes, and lately more times than not, it worth to have a second copy of some Theme to get a second copy or full playset of some playable cards easier, e.g. TEU Charizard, Twilight rogue for extra Malamar and so, or Trainers we all know are staple like Cynthia, Guzma, Escape board etcetera.
If you already have an extensive base of cards to play with and no need of those extra cards even to get locked copies and release the unlocked to get 1-2 packs each, then yes, you can aim to Packs, keeping always some coins close to the date of a new set release to get the new Theme.
Another option is get Pikachu boxes to add them to trades and be over some other disputants. Something valued 3 that everyone offers 2 packs you can add 1 or some Pikachu boxes to make a little difference.
If you also have the available Deck boxes and sleeves from in-game shop, right now I can't think nothing else to spend into than packs. TEU, LOT and GUR seems to be the obvious choices unless you look for something from other set to play with or to as I said, release unlocked copies to get packs in case you get locked ones.
WE WANT LEGACY TOURNAMENTS BACK !!! If you also want it, show your support http://forums.pokemontcg.com/topic/55966-feedback-making-it-easier-to-get-the-cards-you-want/
5th day reward packs list http://forums.pokemontcg.com/topic/56679-5th-day-log-in-pack-is-random-got-a-gur-dd/?p=593037
Foro en español, también existe: http://forums.pokemontcg.com/forum/2-español/