I find BCN interesting since it is the original CryptoNote cryptotoken that first implemented Ring Signatures. Surprisingly (or not so), Ring Signatures / Confidential transactions is a feature that Steem is looking at implementing at some point in the future (see this portion of the road map https://steem.io/roadmap/confidential/).
First to market (minus the ridiculous ninja-mine -- or was it insta? -- by the CryptoNote developers, and some other shadiness with mismatching dates on the original white paper) often has an advantage. Either way, we may not have seen any implementation of Ring Signatures in a cryptotoken for quite some time if it hadn't been for the people (or person?) behind ByteCoin.