I haven't been to a ton of parks either, but these would be my top 3:
1. Busch Gardens Williamsburg - The first park I ever visited, the park I've been to most, and a place I'll never get tired of. Highly immersive atmosphere, wonderful theming and landscaping, and a quality selection of rides.
2. Universal Orlando - IoA and USF are easily the best themed parks that I've been to, and the Wizarding World of Harry Potter is by far the best themed area of either park. Hulk is one of my favorite coasters, and Harry Potter, Spiderman, and Men In Black are my favorite dark rides. Citywalk really adds a lot to the atmosphere and the fun of the resort as a whole as well. My only knock is that it seems they have little to no room for expansion, so new rides aren't as frequent since they mostly only come at the expense of old ones.
3. Tough choice. I'm tempted to say Kings Dominion since I've always had fun there and it does have my favorite coaster, but I'm going to go with Dollywood as the overall better park. It's got a really great feel and atmosphere to it, very genuine and welcoming, and the friendly staff contribute heavily to this. It's got great food, especially if you love barbecue, which I do. It is relatively small and has comparatively few rides, but Thunderhead is a world-class woodie, and the other rides complement each other well.