Yep, I really like using surround on the echo. However, at its core, the echo effect is just a delay. There is no way to turn it into reverb.
A few things you can try to make it sound more like reverb:
Use remote commands to add a small release fade to instruments. The release fade can hide the echo a bit.
Use two copies of a channel, with the second copy being quieter and slightly behind the first. This is often called fake echo, and can help fill out a melody and hide the artificial qualities of the snes echo.
The fake echo can either be just a few ticks behind to create an early reflection kind of sound, or a larger distance such as an 8th note, quarter note etc. to give an actual echo effect. Both have their uses, depending on what you want to do. Using slightly different tuning, vibrato and adsr on the fake echo helps too.
But these are only tricks which sometimes work. They can work very well in stuff likethis
, but I made that port specifically to experiment with turning the echo into reverb, and as a result I was able to approach it differently. Most normal music wont' be able to make such extensive use of these tricks, so you'll have to do what you can. Often, tweaking the delay time of the echo is at least a good start, since different flavors can be achieved with different delay times.
Make more of less, that way you won't make less of more!