Yes considering that. As well considering grafting some improved varieties of paw paws and persimmons on some of my trees that are already growing. I beleive persimmons are dioecious and would like to get more fruit on many of the persimmons so considering grafting those. Not sure on the paw paws but I have a ton of root stock and trees growing about 20 foot tall that don't produce any fruit.
That may depend on the tree, the fruit and any pruning. We grafted some pears about 8 years ago. They were getting that tall.....no blooms or fruit..... then last year, finally bloomed and set maybe 8 to 10 pears per tree. This year, they have about 1 bushel each and are getting pretty tall. Have a Liberty out back that is at least 5 years old and this is first year it produced anything. Semi-dwarf tree pruned into open vase shape.
Either way, going from a small tree planting to producing tree requires some care, and at least 3 to 5 years before any fruit sets. But you probably already know what.
BTW, for wildlife, I'd probably use a semi-dwarf root stock. No support needed, larger trees, longer lifespan, but will be 5 years before you see any fruit.