Japanese maples (obviously!) but get several different sorts
cannas
dahlias (bishop of landaff)
nasturtiums
berberis
loads of tulips, lilies, crocosmia
cotinius coggygria
godetia firelight
poppies (papaver comm. 'ladybird')
astible
heuchera
thistle (cirsium rivulare 'Atropurpureum' is really bright!) or 'Cardoon'
Sedum
japanese bloodgrass
runner beans, tomatoes, chili pepper,
Surely she'll need something to tone it down abit though? Abit of green to relax the eyes, or at least something like Cineria or festuca grasses.
Too much red can make you aggressive you know!!