Adioso was amazing! It was the only flight search engine that let explore possible trips (rather than just looking up flights once you knew where you wanted to go) by searching for regions or "International".
Question for you: can Google Flights (or any other flight search engine) give you the same kind of search capabilities/answers/experience you got from Adioso?
I've looked for other booking sites that helped me determine where I want to go, but haven't found anything else similar sadly.