Dogwood I have. A relative owns a tree farm in Caroline Co. and I have Dogwood and Holly from there.
The Holly has a yellowish tinge so even if there was interest in marketing that difficult species, the available
strain does not seem to be a desired one. For me, even the billets that have Blue Mold should be usable,
since the pure white version is not really appropriate for any ship timber.
The Dogwood was about as large as that species gets, so my billets are fairly large. Not large enough for
frame timbers at 1:48 or 1:60 scale, but I could use it for most any other part.
I am not sure that Crab Apple is all that different from regular Apple wood. One species that may be surprisingly
useful is Bradford Pear. It has anything but fine tight grain, but it is much harder than Black Cherry to carve,
does not want to split, and has a wax-like nature to it.