Zinnias do well in the heat, also Salvia, and Marigolds. But these should be watered daily. Try Cyclamen in the winter, the will actually come back the next winter.
I completely lack patience and commitment when it comes to gardening. But I recently started growing my own edible sprouts - in mason jars on my kitchen counter in my air-conditioned house. Germination to harvest: 5 days. Short-attention span gardener here!