One more lesson learned from the recent balloon chasing is that finding a large pink foam cube in the middle of a field isn’t as easy as it sounds, even if you’re within a couple of dozen metres of it.  This might be mitigated by installing a noise maker in the payload package might make them easier to find. If they had something like a piezo electric beeper, or the siren from a smoke detector, in them that sounded for 5 seconds every minute it would give you something to home in on when the payload is on the ground/in a tree/floating downstream/whatever.

Weight being a concern when you’re launching things to the edge of space, such a noise maker would have to be very miserly in terms of its power requirements so that the existing power supply could be used rather than requiring a bigger – and thus heavier – one.