The reason gardeners grow seedlings is to get a head start on planting their crops so that over the season they'll have time to produce. In your case in a week or so you can just plant in the ground. Here in Pa I don't really grow many seedlings, variety wise. I need to grow tomatoes, peppers and that's about it. I could grow cantelopes as seedlings or lima beans, or sweet potatoes. But we don't grow them here, they don't do well. Maybe I
should take a new look at them.
In your case you could just plant all of the above in the ground. The problem you have is will your plants produce before it gets too hot. I'd just plant out the seeds you bought and again when it begins to cool plant some again for the fall.