The positive coments are great, I really feel like this event has a really welcoming community. Kudos everyone.
But for me, it was comparing my submission and other submissions - how people take different ideas, how people work in a different way than me. Learning from others and improving myself. To give a more specific highlight - it was every time I got surprised by a song taking an interesting turn.
Oh, and the most rated submissions are really good. Totally different to what I would have done, but they are definitely memorable.