Mihiretu has elaborated on his rating system. Now we get not only "I like it" but "I hate it". It is, however, voiced only when he's exaggerating for comic effect. As in "Too-pay (toothpaste), I hate it", while cantering around the living-room just before bed. As yet, it hasn't been used to hurt feelings. Though I'm trying to emotionally prepare myself, just in case.
Generally, things between him and me have been infinitely better. It seems all that praising is doing its magic. The other day, I told him (as I do on the hour) that I loved him. He replied, as he often does, "I yuv you," and then added, as he always does, "I like it, Daddy." And I agreed. I like Daddy, too. But then, after a moment's thought, after seeming to weigh Ben and I in his mind, he said generously, "I like it, Mommy." Triumph.