I think it would be nice if tags of interest had some kind of an indicator letting you know a post features a group of them or something like it. I put together a little example of what may work well, especially if users could customize it in some way. In this example, the symbol could appear once a certain number of tags are featured (or a specific group) and can grow based on how many tags of interest it has beyond that. Perhaps instead of growing, it could instead change color or symbol.
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