It's not flawed because power creep is evident in Rebellion. It could be worse, but it's definitely there, and realistically there will be more of it in any upcoming mini set + future main sets. I think early investors deserve to have the chance to remain competitive in at least one format if they put thousands into the game, without being expected to spend more every year or two. They might have some strong Alpha or Untamed cards but not have spent anything on Rebellion or CL and therefore even with LOD or SOTF they might lack enough cards to keep up with Rebellion's meta changing abilities. I say this by the way, as someone who only entered the game at CL so most of my deck is CL, but who has picked up quite a lot of Beta and Untamed cards yet only has a single Alpha card.