I completed this FM 2 times, once on Expert difficulty and the other on Mestro. "Twilights over Drifstone" is a great example of a fun mansion heist of reasonable length that doesn't "lock" you inside a single place for the majority of a playthrough.

The level, including the outside areas, looks great and is filled with intriguing secrets and multiple paths toward the primary objective. A point of contention I see about this FM is the abandonment of the horror sewer section, which starts with a downtrodden area that, in my opinion, looks better than the majority of other outside areas in FMs. Indeed, the premise may trump the execution because we tend to remember the incomplete better than the finished. So the mansion would get overlooked by people who think the poor district and the sewers might have provided a unique experience.

On the other hand, the mansion has an interesting, but unusual layout. A small issue I encountered is that the lack of a map led to me not tracking properly what rooms I hadn't visited, and a few extra reloads double checking corridors. In situations like this (where hard realism is underutilized), I think it could be helpful to have a map of the interior placed somewhere inside- like Dishonored 2 did for the Institute level. The mansion has multiple entry points, but a few dead ends that could have been better utilized for shortcuts.

As a fan of Mysteries of Tolham, I appreciated the usage of supernatural elements. Other small stories take a few seconds to take in but add much to a mission's memorability, like the poor, Pagan family sleeping in a hovel, or the person killed by an unfortunate fall.

This FM is a great package, and wouldn't mind if the next FM was set in the same world.