What's more, it seems that the quality of the establishment can be determined by the elaborateness of its roll offerings. I've seen preparations of dragon rolls that were truly astounding, and who can ignore the ultimate in the specialty roll, the Rick roll (made either by sushi chefs named Richard, or by severe Internet jumkies, and ordered almost entirely by the 4chan crowd). Yet I've also seen some really simple specialty rolls: the sushi bar in the Land of Uh has as a specialty roll a variant on the California roll, using cream cheese instead of cucumber. It's fattier than your average Japanese sugar cube, and its texture is much thicker and more consistent. However, you simply can't eat it with soy sauce, horseradish paste dyed green, and pickled ginger*, because dairy just doesn't mix with those things.
That said, there's not much you can do with non-roll sushi. It's just seafood of some nature on a bed od short grain rice and secured with green horseradish paste (because almost nobosy in North America uses wasabi). It's rice (pure sugar) away from being sashimi.
But when set up with edamame and miso soup, even the most routine sushi becomes an awesome meal.
*And in saying this, I'm reminded of the scene from Lucky Star where the girls take a quiz to determine what kind of sishi they are, and Konata gets pickled ginger. As Kagami begins to taunt her, she exclaims, "You can't have sushi without pickled ginger!". Oh yes you can. It's strange and uninspiring, but you can.