Hive's multiple private keys is probably one of its greatest strengths.
Even so, onboarding is certainly a big challenge, and will remain so for the foreseeable future.
This added use case ($HBD Bonds) is not geared toward average users, though. This would be meant to appeal to accredited investors and investors who are used to paying advisors and consultants to handle the day-to-day details associated with their investment portfolios.
One thing is potential target of such system, the other is potential influence on other users. If it won't be possible to explain easily, it's going to be seen as old fashioned shady financial shenanigans. It's about perception here. Explaining Hive tokenomics to an avarage person right now is borderline possible.
Let's weight costs and benefits here.
Although, I need to add, personally I find proposed solution appealing.