Lasting that long seems like more than a two dot recipe can handle.
Not sure if permanence would really help that much either in the rhetorical sense. Maybe it looks less like drugs, but now it's a bigger deal and beyond the scope of their local magical expert.
Harry could probably at least envision something that fills your need for sleep for a week, but a potion that permanently or annually satisfies it is a bit much for him to speak on.
If it's allowed we should exploit it, but from a meta perspective even that limitation raises the question of why Molly couldn't just fill a notebook with effects she wants and get all canon recipes by asking how to achieve them with alchemy one page at a time.
Which defeats the point of the ruling stopping us from just doing whatever ritual of our tier we want at an increased difficulty.
Do I like the idea of being a broken super alchemist? Absolutely. But if it's a balance problem to get it with no effort than it's still a balance problem with this approach.
Maybe we could ask to see someone else solving the problem, and then get some sort of cost reduction on the research that doesn't completely eliminate the cost? Seems like it could be a far way to control the crown's interactions with this topic without completely making it useless or breaking the game.
Edit: should have refreshed before posting.
@DragonParadox is the idea I outlined here viable, or should we entirely avoid trying to cheese the crown this way?