First up, I have no idea if anyone looking at playing in my game looks at these forums, but if you recognise this username and are in my game, go away

So! My game should finally be getting off the ground soon, and I figured I'd put down my plans here for people to critique and give ideas/advice on.
Around fifty years before the events of the books, the Head of a moderately successful house purchased a large amount of land near the outer edge of the inner dominances and moved out there, putting out a call to his House for those who wanted to seek their fortune to follow him.
What he had bought was a large piece of land (plantation, small mine, mansion etc) belonging to another house that was destroyed a century ago for attracting the ire of the Lord Ruler. At his word nobody had been permitted to inhabit it for the last century, as a symbol of what happens to those who displease him. While most snapped up the fertile lands and large mines that the family used to own, this house head (really do need to come up with names) bought the now decaying and crumbling 'personal retreat' of the house head, located away from his productive lands, though the rest of the house doesn't understand why.
The PCs will be (some of) those members wanting to seek their fortune who follow him, and each will have some kind of conflicting/contrasting loyalty than that of the party/house, just to keep things interesting.
What the PCs don't know is that the person who attracted the Lord Ruler's ire was an extremely intelligent Mistborn heretic who went mad in his later years. His house achieved wealth by running the Pits of Hathsin for the Lord Ruler (the head of the PCs house is aware of this part, and believes there to be an Atium cache hidden somewhere in the land he's bought) but he wasn't happy with TLR's restrictions, researching forbidden technology, trying to find new Allomantic metals, discovering rudimentary Hemalurgy and most grievous of all, cutting free a number of Atium crystal nodes from the Pits and secretly transporting them to his retreat to see if Atium would grow there.
Ruin's subtle influence, combined with the distance from Luthadel, meant that these things remained hidden from TLR for decades, allowing him to develop his skills, a number of Hemalurgic creatures, discover some "New" Allomantic metals, and some "rudimentary" technologies like crossbows, gunpowder, electricity etc
All these are sealed in a complex multi-layered vault with clockwork locks keeping each section separate. The party will no doubt find this vault, and spend a chunk of their time decrypting each lock to get in and take a look at what's inside, and then deciding what should be done about it.
There will also be some sluething, general archaeology stuff, and dealing with the occasional Hemalurgic creation running around the countryside.
What do people think? Sound workable?