These are the worst meshes in Data and G7's optimisation removed a thousand nodes from each, Have checked only through those present in the CS and world and they seem no stranger for it:
An old Indoril ancestral tomb that’s still occasionally kept clean by descendants, though it should still be a bit dusty and unswept. Overall more cultural and lavish than the average tomb. No activator shrines.
Cell: -4,-19 An Indoril tomb that’s been inhabited by hostile conjurers for some time. Try to make the tomb more eerie and dark than what’s typical. No shrine activator.
Cell: -9,-21 A large Indoril tomb that’s begun to collapse in some places, forcing the player to find alternative routes to all the rooms. Overall rather ornate and neat in the places that haven’t succumbed to the rocks. Can have a shrine activator out of reach of the player (without telekenisis, a potion or something could be lying around in the interior though not too close by), or an inactive one.