4' plastic fencing is enough to keep my birds out (flock below) - they defeat it by landing on the 4' gate, then hopping over. In addition to thornless blackberry (ours are wild, native, have thorns and small fruit, sadly) which my birds like, blueberry will also do well in your soils (we have similar climates, you and I - though you have been much wetter these past two years with the unceasing pounding of the hurricanes - and it takes a while to put on size.
I've had good luck with rosemary, once its beg enough that they can't break off low branches by tripping over/thru it (more a problem with the ducks, who like to nest and lay eggs next to it).
A final consideration, though again you are looking a couple years down the road, would be to build a grape arbor with posts and wire, a handful of plants. The first year, it should climb the post and begin down the wire before freezing back. The second year's growth might get you 6-8 feet down the wire, but not much shade below. By the third year, you should be seeing fruit, good shade projected by each wire for most of the 12-15' length during the summer and fall. Mine love the fruit (of course - we have wild muscadine, plus some varietals I planted deliberately) - but completely ignore the vine and leaves.
If you'd rather do trees - look to serviceberry and jostaberry, but check your needed frost hours, you may be borderline on those.
I have about a good acre of blackberry (so about 1/4th of the property) and have to actively trim it back from spring through fall - if I don't it'll eat up my driveway.
