The photo at the top of the post is salmon wrapped around salmon roe on rice. It's called oyako gunkan, or parent-and-child roll. This is something you don't see that often even in Japan, but it ought to be a classic - it's hard to top the combination of smooth, sweet salmon and the bursting-bubbles texture of the salty little eggs.
Here's an example of the sushi chef's creativity. The fish is kodama, a small blue-fleshed fish similar to sardines, with the same rich, briny flavor. Braiding it doesn't change the taste, but gives it flair and sets off the pretty leopard-spot pattern of its skin.
Last, a delicious example of the native spicy tuna roll. No mayo or hot peppers, just tuna ground to a smooth pulp paired with crunchy green onions - a perfect contrast of colors, textures, and flavors.
We ate many more pieces of sushi besides these. In Japanese sushi bars, the single pieces (nigiri-sushi) are more prevalent than rolls (maki-sushi), and the spicy tuna was the only roll we ordered. But it's easy to go overboard with nigiri - each fish is so different and so fabulous that I always try to taste them all. But fortunately, having already been to the Sendai branch twice before, I had narrowed it down to my favorites. The three tunas, the salmon-ikura combination, the best of the blue fish - mackerel, horse mackerel, kodama, sanma - and the seared fatty salmon, plus one spicy mentaiko (the tiny fish eggs sprinkled all over American sushi) for Yuri, and we were stuffed. So stuffed, in fact, that we didn't even bother to have dinner, just a shared berry parfait at an internet cafe and a couple of beers at karaoke later that night.