Hmmm, I had assumed this would be a night display and that could be battery powered, but I guess the certifications are probably different, so you probably want daytime use. In that case, just do it with cables, and since the cables are for power delivery, you just need a controller at each power distribution node and the display dots can be 'dumb'.
For example, if you have 10 nodes over your 5 acres so that you can keep any individual node to light run under 100 feet (if that's how the space works out), then each node can control them individually (a big pain), or can control a few channels worth of lights, with each channel turning on the ones required for an individual animation frame using a relay or something. I'd drive the light "pixels" with a reasonable AC voltage (maybe 24-48VAC) to keep the cable losses to a minimum, but then with 10 main nodes or so, you can have larger power sources for each, or you can connect them up to some grid power source.
With such a setup, you could still use your preferred wireless tech with the base stations, but you could probably program them and just let them run since it would only be 10 units worth, provided you had a synchronization mechanism to keep the animations from drifting apart. The base station would probably be custom, but then I'd look for a commercial waterproof light with a spike to drive it into the ground or something, and a similar outdoor rated cable with waterproof connectors. That way the connectors and lights are all done already, with just the base stations to worry about. Once you know specifics of the lights you're using (and it's probably worth testing them by hooking them up and flying by to see if they're reasonably visible), you can determine acceptable cable losses, cable expense, and site dimensions to tell you how many nodes would be needed.
Still a large scale fairly complicated project, but I think centralized control would be a lot simpler unless you can use low power (only nighttime operation) and need individually configurable pixels.