I only played the Game Gear version... but I hears the sountrack was beautiful.
I also heard the name derived from John C. Lilly, a controversial scientist who believed in an alien organization called the Earth Coincidence Control Office or E.C.C.O. and was also noted for his work with Dolphins.
It's actually a coincidence, but a coincidence that Ed likes since he also likes John C. Lilly.
Ed's boss Clyde Grossman was the one who named it Echo which then Ed changed into Ecco because Ecco's speeling is more likable than Echo.