That sounded really good until I reached mushroom. I don't have anything against mushrooms, but I remember having a piece of sushi with mushroom--it was just a strip of mushroom over rice wrapped with seaweed, rather than a roll--and I wasn't particularly impressed with it. Maybe with the eel sauce it would improve.
Speaking of which, do you (or anybody else reading) have a clue what's in sweet eel sauce? It's one of my favorite sauces, and it seems to be reasonably standardized everywhere I've had it, so there's a definite basic set of ingredients and preparation involved. I've never managed to make anything even approaching it in flavor.