It's really hard to choose one as they are both very crucial. But how about tracking wallet activity and where funds are moved to and from? That doesn't infringe on privacy, right? Especially as Blockchain technology is already very open/transparent. Maybe this route of tracking wallet activity more efficiently can be a good means; but then, like you said, we don't know what route Metamask plans to take. Maybe they wouldn't disclose it and I think it's better that way.