Oh, I wish I were closer! If any of you have the space and $, I'd encourage you to add a few. I love deciduous azaleas!

I own several Weston-bred deciduous rhodies and azaleas among my deciduous azaleas and really like them. (They are all genus Rhododendron, but there's something about the flower form that differentiates the azaleas and the rhodies; I haven't tried to keep it straight since they are all lovely.) They bloom in either spring or summer, have striking colors, and many of the summer ones are scented rather like R. viscosum, sort of vanilla'ish. Most also have autumn foliage colors in the peachy, gold, or muted red range.

I'm not sure what is currently available, but I have 'Golden Showers' (Weston hybrid) which is blooming now, in peach and gold.
'Weston's Parade' blooms a bit later in July and has medium-dark pink scented flowers.
R. viscosum, a native species, is blooming now. Mine is a pale pink, but it is most commonly white. This is an unusual rhodie in that it is perfectly happy with wet feet, though I also have it growing in average moisture.

Blooming in spring, I have
'Narcissiflora', a Ghent hybrid with double yellow flowers
'Northern Hi-Lights', an Exbury hybrid released by the U of MN with white flowers that have a bright yellow blotch on an upper petal. It blooms well in only a few hours of sun for me.
My earliest blooming deciduous rhodie is rhodora (Rhododendron canadense) a wild plant with lavender flowers that bloom before the small blue-green leaves emerge. This one also likes wet feet. It isn't commonly found in commerce, but I love its early spring flowers and slightly frosty summer leaves.

Golden Showers is there - as is Millenium....Frank Abbot....Weston's Firecracker and Weston's Sparkler. Not sure if there are any more - if I go back I'll update.

I have a couple of the earlier blooming deciduous azaleas - Exbury Klondyke and Knap Hill Buzzard (poorly named but it's my favorite because of its graceful arching habit).

Oops, I forgot the photo of 'Golden Showers', which in my garden isn't very gold, much to my surprise when it first bloomed. Mine grows in mostly shade with just late day sun so maybe with more sun it would be paler in color.