You can always sacrifice speed for security. I like this design which was used to manage bitcoin: http://trilema.com/2013/mpex-tech-stuff/. Blockchain is a way of creating distributed ledgers. The rest is ideology. If you are making a publicly accessible API you can chose how to implement it. Regulations were applied to digital cash but given more run room with crypto.

It seems like Chime, Rho and a few others from the article are built on said APIs.

Paysera out of lithuania. Mr Tango. there are a few