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My raised bed soil (picture below) is very productive. It holds water & air well, and is full of soil life, but there was a LOT of shrinkage in the first years because it was mostly organic components. You can see some sand & Turface in it, but I think I'd be sure to try to have at least 75% mineral (inorganic) content that won't break down. For you, that might be fine sand, or even some/one of the Turface products that is finer than Allsport/MVP. Over the years, I increased the mineral content by adding the fines left over after screening Turface Allsport/MVP for the gritty mix. Topsoil would work just fine, if it's decent.
I mulch my raised beds every year with pine bark. I don't till/trowel it in - the soil life just seems to break it down slowly. That's what I would do with the larger pieces after you have your plantings established.
Watch out for some N immobilization the first year (with that high a % of organic components). You'll probably need to water a little extra, and use a high N fertilizer, but after the first year you won;t need to watch so carefully. Keep an eye on leaf color, & when things start looking a little chlorotic, it's probably time to fertilize.