Treesong, I don't know if the following is of any use to you, since I only know about herbaceous perennial gardening in our zone (5b).
I do maintain all of spring-, summer- and fall-blooming perennials in the same perennial beds and aim for blooming throughout the growing season. The plants are relatively closely placed in the flower beds and I find mulch just gets in the way of ongoing maintenance. I avoid species and cultivars that spread vigorously, including a number of those you mention. Despite that, some reduction in the spread of some summer- and fall-bloomers is often necessary, for me, at the end of the fall. I'm continually cutting back perennials that have bloomed from summer on. I believe that it's especially important to do this in early Fall; the latter to expose (to sun and rain) spring-bloomers that have spent the summer protected underneath taller summer-blooming plants.
Spring bloomers which have worked well in our garden (viz. at least here) include lungworts, primulas (Polyanthus type) and brunnera. I've also added hellebores more recently. A few ephemerals (spring blooming and are then gone) have worked well, especially Virginia bluebells. I find the spring-flowering anemones I've used (Anemone ranunculoides and A. robinsoniana) get to be spread around too much for my personal liking.
Re spring bulbs: currently I only add the first to bloom; namely, snowdrops (not eaten by the voles)..
Approximately the same location in the flower bed:
(1) May 3, 2021 (Fall monkshood at back).
(2) Aug 7, 2021 (same Fall monkshood at back)
(Peonies on either side at the back.)
