It's not like all labels are 70mgrams, but anyhow. Keep in mind that there's people out there (myself included) who do fly a lot in second and third world countries. And if I lost my drone/iPhone/Rolex in any of them, I wouldn't expect it back, no matter how many tags I put on them.
I’d advise just putting one tag (or label) on your drone. I can’t see any reason to put on multiple tags. I don’t understand your comment about third world countries. I can’t see why you’d be any less likely to get it back. Your mobile number might not be enough, as the dialling code might not make sense. But in those circumstances, you could write your surname and the hotel you’re staying at. Or whatever contact arrangements are relevant at the time.
Either way, the fact that you sometimes visit other countries doesn’t preclude you from using your mobile number when you’re in your home country. The point is largely irrelevant.