[@TTNoobs]Personally, I'd be willing to try with as few as four or five.  Basically, my thought is if we have enough to split into two groups due to plot point or terrain obstacle we should have no trouble strategically and that would allow 1x1 personal interaction and character development as well.  Skyrim dungeons are designed to be completed by a single person with a follower.  I know that roleplays are very different from the inspiration material but we should still be able to at least start with a diminished number.

In fact, as an option to consider, if we have two argonians then we have a pair that could use any of the flooded areas to bypass traps and most of the falmer.  It would be possible to start in two pairs that don't actually know about each other yet.  The argonians would take an early opportunity to use a flooded route and avoid trouble while the other group would have to fight its way through.  They could meet up at one of those large open areas with the high walkways.  Either the walkers could be knocked off and fall into the water or the swimmers could use ranged attacks to defeat a falmer ambush that the walkers were caught in.

These are just ideas that occurred to me.  It's your show but I figured that additional inspiration and options wouldn't hurt.