Tentatively, that was the idea at present. I had planned to present it as a state of death that is not necessarily linked to heaven or hell; so yes, a limbo of sorts I suppose.

But yes, I am aware of the potentially dull interpretation of the setting thus far. Naturally an interest check is just a medium for preliminary ideas to develop, and the 'crypt' archetype was admittedly the first I had envisioned, there will be different environments. I had plans to build it outward from a world that is reminiscent of a standard fantasy world, but permeated with an overriding sense of wrongness; empty for the most part, and equally dangerous. I hadn't considered any concept art to work from in terms of the environments design so far, but I will be on search of some. Most of what I had planned was mostly derived from things like Dante's Divine Comedy, a couple of past roleplays, and some slightly darker novels I have read recently. 

There will be a plot; I think it would be irresponsible not to have one. Naturally it will come from the characters that join and the fleeting memories they hold on to. Other than that, naturally I don't know any more of that aspect at this time, but there will definitely be a goal in place. There will be motive, and it will be interesting.