MrRobot
In doubt there's always the Sun!
If what Hero said is what I think he said these crossbows may be too cumbersome to actually act as PD systems.There's flying mutants, if they are still fleshy they can be hurt by crossbows and I imagine smaller drones might get crushed by the sheer kinectic force.
And I would like laser weapons for point defense, but we don't have any.