We visited Caddo Lake for a weekend during July, and found it to be a pleasant experience. You need to reserve a campsite and register your vehicle for a small fee, which was pretty reasonable. Although most of the campsites were full, it did not seem crowded in the camping area, and we were still able to get a spot next to the water. During the night we could here raccoons and other critters crawling around, as well as fish (and maybe alligators?) If you look close enough, you can also see your neighbor's campfires. The park has nice trails to hike, albeit short, and there are old remains of brick structures which are cool to take photos with. The water itself is kind of murky, but the trees make for a spectacular scenic view. You can rent canoes and paddle around and fish, or you can fish from one of the piers which extends to the middle. We unfortunately did not have any luck, and neither did anyone we talked to, so fishing doesn't seem too great here. A cool aspect though are the alligators. If you walk out on the pier at night with a light, you can see their eyes as they swim around.