At the very least there should be the 4 icons to change locations but also would be great if there was a drop down for previous locations. It quickly gets very tedious moving around.
MP3 support, now the codec is free why not? I would find it very handy for exporting a mix ready to put on my mp3 player. Other formats would be good, ogg etc.
Some kind of queue support would be good if more formats are added, like in reaper where you can set up multiple exports to happen in one pass.
When setting a pattern selection to export, highlight the area being exported (or darken/blur the unexported areas).