Two mentions of "pass it down"...
What a lot of people don't realize is you can "pass it down" for no cost even if registered to an individual. It's done via a Form 5 and either goes to the lawful heir (spouse, child, etc depending on the circumstances) or to whoever is named in the Will for the particular item(s).
So, don't use that as a decision point either way. It's pure internet rumor to think the ATF will collect your NFA items and destroy them when you die unless they're registered to a trust.
The NFA game is not for the impatient. I wouldn't let the approval duration really sway your opinion. For the most part, these are lifetime investments, so several months shouldn't matter...if those timelines even stay consistent. The potential return of EForms is always out there, and the ATF has said they're working on it.
The main advantage of applying as an entity is the ability for multiple people to possess the items. That alone is reason enough for me.
The paperwork involved for an individual vs a trust with a single RP is basically the same. As a trust, you simply split the answers between two forms instead of putting in on one. (You skip part of the F1/F4 and answer the same questions on a 5320.23 RPQ form instead).
If you went with a single RP trust, you'd have the ability to add additional RPs after the fact without any notification to the ATF. You could repeat that practice, and never have anybody else provide photos or FPs. Just food for thought....