Wonderful top! I like your idea to SITD around the letters and then stipple behind them to make them puff a bit. That will make these areas fairly dense so you will need a good amount of quilting in the quilt body so it's consistent. You could SITD around each block and then do the same Bronc outline in each block? It won't be noticeable in the front but would look neat on the back if the backing is plain. An all over large meander in a gold thread would also look good.