I believe there is a natural cycle of convergence then divergence. Pools came about simply because it afforded each individual a better chance of mining a block at the expense of a little sovereignty. As pools consolidate to peak levels, certain pools will undoubtedly make policy and decisions that go against individual morals or preferences. Those pools will lose users as they migrate to solo mining or smaller pools where they may have more say. Miners will sacrifice hashpower for more sovereignty. As this process of divergence reaches a peak, we will see another reversal as people ban together again for increased collective hash power at the marginal cost of sovereignty.