Roses with glossy leaves fare better against fungal diseases like powdery mildew and downy mildew, but when the weather is wet and humid the conditions are ideal for the fungi to grow.
Roses are high maintenance and for the most part require regular, pruning, feeding and fungicide and pest control.
Plant them near a street light, it deters rose beetles. Plant four o'clocks and/or garlic under them. That will also deter bugs.
Make sure the plants are well spaced and they get good air circulation and they are not planted up against solid objects like walls which will block air flow.
I use systemic rose care on my roses when the weather is hot humid and wet. It works well controlling blackspot, powdery and downy mildew and deters most sucking pests. It lasts for about 6 weeks. I disbud my roses when I am treating them since I want to minimize the harm to bees and other beneficial insects. When I look for roses, I try to buy ones that have glossy leaves and not the ones with matte leaves.
Baby blanket, a landscape rose, and red buttons, a rambler, are so resilient that not only do I not spray them, they grow like weeds. Hybrid teas are going to be the fussiest roses.
My winner tea roses are Peace, Queen Elizabeth, Iceberg, Mr. Lincoln, Chrysler Imperial, baby blanket, Neil Diamond, Scentimental, Proud land, Summer Fashion, Red masterpiece, Julia Child, Electron, and Chicago Peace. These have lasted the longest.
Simplicity also has survived since 1991 in my yard, and that is quite a feat. I am down to two from the eight that I had, but they pretty much are carefree roses.
Here are more suggestions for disease resistant roses.
https://extension.oregonstate.edu/garden ... tested-pnw
Happy gardening in Hawaii. Gardens are where people grow.