Suggestions for new orchard options

I have a polyculture orchard right now with mulberries, apples, cherries, peaches, pears, Asian pears, Cornell dogwoods, elderberries, bluberries, Autumn olives, figs, and now Asian persimmons. (We natively have large American persimmon trees.) Any suggestions for odd or unique orchard trees in heavy clay soils? Thought about pawpaws and Utah serviceberries. However, we have stand of thousands of pawpaw trees nearby. Are there almonds that can survive -10 winters? Maybe Jujubes?

There are some sweet pit apricots that can withstand the cold but your production will be iffy just like the peaches if you routinely have late frosts

Look at all varieties of Persimmons.  There are American Asian Crosses as well as Ukraine and American Hybrids.  Go to nuttrees.net and shop in the fall when Cliff has restocked.
Mulberries, Goumi, Pawpaw cultivars so you can graft them to the wild trees.  Yes on Jujube.

Che (aka Chinese mulberry, zombiefruit, cudrang, melon tree)
Aronia berry
Blackberry

Matt, how does Che taste? I have heard nice and others say they would not bother with it.  I expect a lot depends on variety and environment.

Goumi, medlar, grapes, good tasting hawthorns, asparagus.

On average, our weather is probably similar to yours, but you are hotter and colder.

John S
PDX OR