I've legit been thinking about this since i posted the comment lol. I think the target area should probably be a minimal regular hexagon, but I honestly dont have the mathematical chops to figure it out myself or to know which would be more interesting.

Intuition tells me to either try to reduce the problem to like convex hull or figure out a reasonable way to generate random packings and just monte carlo it a few million times for a close to optimal solution. A reasonable way to generate random packings feels like it would be way harder to implement than it sounds