I think the second and the third as the ones with the most suitable identity. I think the second is the most suitable for a blog based on blurt, the third for the Blurt infrastructure (the Blurt blockchain). I think the other ones as logos without a good identity, but is my opinion only. They are good logos, but with a less strong identity.
Personally, I think that the logo we have now has the strongest identity as a "blog-based product", for me at least. So, I prefer maintaining that one, but I will accept the choice of the community. 😀