The s2400 allows us to send tracks out of one of the individual outs and back into a looper track to create fx send/return loops. I love this feature, I use the s2400 with an sp404 which is connected to tracks 7/8 and loops back into input 3/4. This way I can send any track into the sp for fx by setting the outputs to 7/8 and recording it into a looper track.
I used the octatrack the same way, and one of the great features of the octa is that you can quickly send any track into your fx send with the cue button, which also allows you to change the gain for the cue output.
Something similar would be great on the s2400: a button combo (pan+pad?) toggling the outputs of said track to the outputs you set as cue outputs in the menu and back. It would be even better if you could then also set a different gain setting in the menu for the cue outs.
Hope I wrote this down in a way that makes sense! Great update btw guys!