For most of the plants you mention, diseases can propagate from one
year to the next and so it is best to remove the dead or dying plants
now, including the roots. You have then several options. You can put
them in the garbage, you can put them on the lawn away from the garden
and mow them into smithereens, you can hot compost them to kill
pathogens and use the compost in the garden again, or you can cold
compost them and use the compost in a flower bed away from the garden.
I use options 2 and 4, by using them as mulch for flowers and fruit
shrubs, or just mowing them where I feel the lawn needs a little boost.
I leave less disease prone plants in the garden, however (mostly greens
and alliums), to compost where they fell.
Surely after one year of gardening the soil, specially in the pots, has
been exhausted and so it is a good time now to dump a few inches of
fresh organic matter into garden and pots (I use wood chips, manure,
grass clippings, leaves, kitchen scraps, and wood ash). If the organic
matter is nutrient-rich (manure, kitchen scraps, and wood ash) you can
avoid fertilization entirely next year.