I don't have any suggestions, but think that it sounds quite lovely.

If you are not looking for just named irises, I could send a couple of fans (for postage) of this NO ID one I have. It is however a bit shorter than most TB, but could let you know its exact height for the best placement. It has been a reliable bloomer for me.

lmk if you might like it and when (approximately)

Sue

I think it will be beautiful.

Don't get English Charm. Its standards are yellow, despite what the photos look like.

My favorite is Wabash, but it has that white rim around the falls, so you might not want it for this bed.

I think Sue's yellow is wonderful.

Renee

Chemocurl ~ that is lovely!

2 sites I know have color categories.

Exline Iris Gardens mixes wht/color with ie.yel/diff color but it does narrow the search. Link below.

BlueJ may have similar category.

Here is a link that might be useful: http://www.exlineirisgarden.com/iris/201

Mr. Toad, Iris4U has an amoena page. World Premier's standards are light blue, not really white, so I'd take that off the list.
Renee

Here is a link that might be useful: Amoenas