A next big step would be the implementation of an easy log-in with familiar login methods like Google or Facebook login and a guest account management system, that allows participating on the page without the need of understanding the mechanism of Steem or the Blockchain behind it.

This. It's probably more important to make the onboarding easier than to keep all accounts and all their actions completely on the blockchain.

I also really like the screenshots you posted, looks really good. Finally a tribe that actually changes the ugly steemit.com interface to look more appealing.