Especially for lower level characters, Amphail Asylum offers a fantastic beginning of a campaign, whether setting up character interactions, or borrowing some of the underlying themes to continue running it through your campaign. As a one shot, it does stand on its own and offer a pretty self enclosed story, that you could assuredly make an unforgettable night out of. If looking to use this one shot adventure as a basis for your campaign, this malleable campagin starter offers a lot to subtly drop back story along the way, and you could easily tie another theme that works with its story, to continue past the events laid out in the module. My recommendation would to consider the ending, and one of the choices that you can offer your players, if only because it could affect your grander campaign goals down the line if one doesn't plan accordingly. Very solid work.
[5 of 5 Stars!]