For me, the concept of decentralised trust is the real advancement seen. Decentralised can be achieved in various ways. Bitcoin started sthis with a Proof of Work approach. Meanwhile, there are a lot of other crrypto projects that tackle the concept of decentralised trust in another manner. Sometimes by only changing some parameters to the protocol (this was especially happening in the massive creation of new coins in the 2013 period) and sometimes by a whole new concensus model (currently seen a lot; for example Byteball and IOTA).
The competiton between these ideas and constant will in my opinion eventuallt lead to the 'perfect' blockchain concensus model or models. But that process takes time and will be messy.
Anyway, never a dull moment in cryptocurrency world.