Truth is, collectible is a garbage format for players, always has been. It benefits only the publisher by forcing players to buy product they don't need in order to (maybe) get the stuff they want. Yes, trading alleviates this somewhat but in order to build up decent trade stock you'll be buying a lot of stuff you don't need and can't trade off.
Destiny is the first collectible game I've bought into in over a decade. I hate the format, so the fact that I'm even willing to give it a chance speaks volumes for the quality of the game. However, the ugly reality of the collectible format is already rearing it's head. I've bought 2x Kylo and 1x Rey starters and 6x boosters, a total of $65, and don't have enough product to make anything close to a solidly competitive deck.
I hope that FFG at least a considers releasing more fixed-content packs in the future to offset the drawbacks of the purely collectible content. It boggles my mind that after pioneering the tremendously successful and all-around superior LCG format that they chose to return to CCG.
I call BS on this, on a couple of points. You are blaming the collectible format for your failure to get what you wanted/needed to play "a solidly competitive deck." Truth be told - and I apologize for the harsh tone here - the mistake you made was spending money on boosters off the shelf. You can just as easily - and more effectively - get what you need by purchasing the cards on the secondary market, or by buying a booster box where the distribution patterns are far less random and you know you are getting 6 legendaries. Buying random packs was dumb in Magic and it's dumb in this game too. Save your money and buy a box for $90-100 instead.
Secondly, the LCG format is a collectible format in its own right, it's just that FFG has managed to fool many people into believing it is not. I play X-Wing, and I know you have to buy everything to keep up. I have had to buy several ships in multiples to get cards that I need to keep my fleet competitive even though I know I will never use those particular ships. And those ships cost a helluva lot more than $2.99!