We enjoyed Shutters very much. Due to a little mini crisis, we ended up cancelling our ADR for Coral Reef last December. We had one ts credit left and since it was so last minute my choices were the Plaza in MK or Shutters (there may have been more but those were the two places I knew would work for us). I am so glad we did Shutters. We had a wonderful meal, excellent service and it was a very nice way to end our trip. We were staying at CBR so that made it very convenient too. In a way however, I love that resort so much and enjoyed our meal so much I might go back again someday even if I wasn't staying there. It would be nice to eat dinner there and then take a nice walk around the lake. And you have a very good view of Illuminations from CBR so that could be timed easily.
We also loved our meal at Maya Grill. Really nice evening and great food and service. Again, we were staying there but I might return because we enjoyed it so much. And like CBR, CSR has a beautiful lake to walk around and enjoy following your meal.
POR , a carriage ride and a walk along the river would also make a nice touch after a dinner at Boatrights. I haven't eaten at that one, we didn't eat there when we stayed at POR a few years ago. Wish we had, maybe we'll just have to do that sometime!
I agree you don't hear much about the non deluxe eateries but from my experiences I can say we enjoyed our two meals very much. And the moderate resorts are lovely to walk around after your meal. It isn't just the deluxes that offer something in the way of theming and enjoyment to explore and experience whether you are staying there or not.