After Fenway Star and Washington Square Whole Foods, the next priorities would be the Union Square Target and potentially the Newmarket Stop and Shop depending on other development in the South Bay Center area. In the medium-term, the East Somerville Stop and Shop will probably also go this way as well.
Further out, I'd love to see denser rethinks on the Newtonville Star and Whole Foods and the Waltham Center Hannaford (there are others as well, but those are in the densest areas).
And of course there's the need to build new grocery stores in multi-use developments in underserved (Black) neighborhoods.