Your grapes will sadly never do well, they are both suited for the north (i really enjoyed both of those when i lived in Nebraska). I am in North Texas now, on the northwest outskirts of DFW, TexasPrepper2 (i also enjoy his videos) is more of east Texas, or northeast Texas.
What city are you near? Texas is big and Zone 8 alone isn’t enough to really go by. Fire Blight can be really bad for apples and pears, but that is more in the eastern portions of the state and areas that get high humidity. It feels like once you get east of Dallas, humidity and rainfall go way up. There is about a 10" between Tyler and Fort Worth for annual rainfall! Also, chill hours vary pretty crazily. here is a map: Apples-fig2.jpg (386×357) (tamu.edu)
Pomegranates and Figs are doing well for me. Even when dying to the ground, Figs tend to produce every year. One on my Poms will even produce every year even after that horrid storm in Feb.
Persimmon seem to do pretty well to. I only have Asian Persimmon, but they are too young to produce.
You need to be really careful with apples, peaches, and stone fruit. There are northern and southern varieties of each. If you plant a northern variety, you will likely struggle and not get good fruit. The Texas Aggie Horticulture has some good recommendations. Most of their recommendations are for commercial and less backyard so keep that asterisk in mind. They only recommend Anna and Golden Dorset for apples, both are summer apples. Arkansas Black has been doing well for me, still young, but this was my second year of bearing and no signs of the tree struggling. Ghost has done very well and was highly productive this year. I also have several other varieties, including red fleshed ones, but most are only 1-2 years old.
My peaches have really struggled except for 1, but i don’t know the name of it. My sprite and Delight (2-in-1) tree has done incredible! It gets loaded every year with great fruit and the tree is very vigorous.
Pawpaws only need about 400 chill hours and should be able to grow for you as long as you keep them shaded while young.
If you want grapes, muscadines are the best options. Make sure to pay attention to gender though as you need male and female to pollinate (some are self fertile). Blackberries are another option to consider. If you do some research, you can find some that don’t get too invasive. From 2 plants that are only 2 years old i was able to get about a bushel of berries.
Depending on where you are, Satsuma could work, but every 10 years when we see a bad storm like last winter, you will need to protect them. I keep my citrus in pots so i can bring them into the garage and have them under grow lights for the winter.
And of course, there are Jujubes! These do really well and put out nice crops. If you have never had them, they are sweet with a hint of apple flavor. They can take drought really well too, have no pest or disease issues, and are as close to a maintenance free fruit tree as you can find. if you search on the forum here you can find some variety recommendations. So far my favorite is the Contorted.
