Personally I am waiting for the CL summoners before building my own deck. I am currently renting most of my deck for gameplay.

I guess the question to ask yourself is which aspect of Splinterlands you like more, actual gameplay or the economy surrounding the game. If gameplay is what you are after, definitely investing in cards that suit your play style is the way to go. Also, the cheap CL reward cards are actually pretty good as some of them mimic the alpha/beta versions as a fraction of the cost.