Funny, I went and read volume 2 of Opus today.
The wall breaking in it is pretty amazing. Wish it could have had a real ending, though even the way it ends in is interesting in its own way.
Yeah, some of his other works - manga - are also full of great narratives/visual ideas (World Appartment Horror, Seraphim). He did a great (even if too short) carreer as an animator/director but I will always regret he couldn't also go further as a mangaka.