This is my opinion only, sushi in Dallas is all pretty much the same - no difference in freshness, but there might be some Texas style rolls that are regional (I'm not sure) - I do like the volcano rolls
I agree on Neighborhood Services and Stephan Pyles, but also check out Cane Rosso for neopolitan pizza, Smoke (bbq/brunch), Hard 8 (bbq, in Coppell), Parma (Italian, in Lewisville), Victor Tango (american)
Look around in the bishop arts and trinity groves areas, lots of up and coming restaurants