Brilliance works pretty well, and I've found if you heat set it right away it kind of keeps the ink from sinking into the paper. Also, if the stamp is not terribly detailed, I have used my stamp positioner to stamp over twice in the same spot.
Nothing will equal white embossing powder for opaque white. An acrylic paint will come closer (think that's what Picket Fence is, it's different from the rest of the stains). But sometimes you don't want that look, you want something softer.
That said, what kind of difficulty are you having with embossing powders? Maybe if that got sorted out, you'd be able to emboss and reliably get the crisp white look you are after.
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