Mounding: bush-like cluster?
Might imply left to itself without division.

A good one here is calico aster 'Lady in Black'. Arching stems and purple foliage. Only near-white flower. Tidy at ground level.

Below from three small plants put in five years before,
in their final year. Picture (Oct 13, 2102).

I don't think you can go wrong with Shasta Daisy 'Becky', but it can get pretty tall (40") and it spreads nicely so you can divide to your heart's content.

For a beautiful late-season bloomer, Boltonia 'Snowbank' is great, as long as you shear it back a couple times times before mid-July. Here is one from our old house, upin Chicago. Here in Kansas, they reseed like MAD if you don't deadhead them. And I mean BAD. I'll bet I now have a couple dozen this size in my Kansas garden and I didn't get around to deadheading them last year, so probably removed ten thousand seedlings, no exaggeration. They never did that up north.