Haha, what do you mean by saying "bitcoin is not decentralized enough  ? "
And being decentralized or not does not mean much. Take a look at Ripple. It is Centralized af, and people are still going crazy about it.

And Spacechain, hmmm good luck to you. The idea is good, but not practical at the moment. You can hope to earn some good profit because it will likely be hyped, but not for the long run.