For steak, nothing beats Shula's at the Dolphin. Its not a WDW restaurant but it is as convenient to get to as the Yachtsman's Steakhouse. Furthermore, it serves the 1% of beef above prime. The Yachtsman's Steakhouse no longer serves prime.
For interesting food? Jiko's. While it is touted as African, there are also Indian influences. We loved our choices.
Spoodles was great. Its at the Boardwalk and has a Meditereanean menu. You could make a meal out of the assorted appetizers, we had the roasted goat cheese, margharita flatbread, and greek salad. It was hard to choose. DH had the snapper which was moist and delicious. Better than my snapper at the California Grill. I had the steak kabob, equally delicious. Desserts were good too. Frankly, I was expecting higher prices here. The appetizers we had were in the $7 to $8 range. Our entrees; $18 and $22. Desserts, $6. If you don't have ADRs, get there early.
Portobello's for Northern Italian food. Its in Downtown Disney and it was Portobello Yacht Club. It isn't as good and the menu isn't as ambitious as it was in the past, but the preparation is still great.
Boma's has the best buffet because the soups and salads are so good and everything else is interesting; except the desserts. I don't like buffet desserts but that wasn't a big deal.
Teppan Edo in Japan in Epcot. This is one of my favorite Japanese restaurants. We have few at home that are this good. Lunch used to be "cheaper" than dinner. Now it all seems to be the same price. They aren't hurting for business these days, so they don't need to lower the price.