What will you get rid of/want to try?
I've taken it less personally when something does poorly and rationalize there is something else out there ready to fill its roots.
monarda's (love them until humidity kicks in)
Penstemon (husker's red must need to be divided?
looks good for a couple years? Mesa kicked the
bucket just when I grew fond of it)
Phlox (the mildew magnets, some are better and still in my
Salvia (technically they thinned themselves out upon dying)
Hostas? do they fair better in pots that you can move around?? mine are great until about July, and then they are miserable. maybe they need deeper shade?
I've moved towards shrubs as of late and special perennials.
LOVE: African Blue basil, verbena bonariensis, viburnum shrubs, miss kim lilac (in dappled shade)HYDRANGEA'S!
Must have roses, even if they are work