Saskrotch, I don't know if this would suit your needs, but I've thought about adding a playlist mode to LittleFM. Already now, you can press sel+start+B+A to get exit LSDj and get back to LittleFM. So what I was thinking about doing is adding an option to auto-load the next song when you press sel+start+B+A. Add t that tha LittleFM is heaps faster than LSDj's own file manager.
You'd still have to press sel+start+B+A at the end of the song, and start when the new song has loaded, but at least it would be a lot smoother. Actually, already now, LittleFM makes it easier to advance to the next song.
I know it's hard to get started with LittleFM, BTW. I need to write a proper patcher already, so people can apply it to any version of LSDj they want.