I had a suggestion set for the spell Greater Sanctuary, due to the complaints usually tossed around because of it. I myself had not too long ago come into the ability to cast the spell, and agree that it is grossly overpowered and rather setting-breaking being able to simply whisk yourself into the Near Ethereal with no consequences as to whatever actions you were currently undertaking. (though a DM might be able to work otherwise)
In the Ravenloft setting, using greater santuary projected you into the near ethereal, where all manner of horrific ghosts and ghoulies could be found, and often would, -find you-.
I just had a thought that perhaps a script could be implemented to check for casting of greater sanctuary, and any subsequent spells cast under the influence of (heck, maybe even any actions taken, walking, opening doors, etc.) to add a cumulative 1% (random number, but it should stay at least fairly low, as it is cumulative) chance to draw the attention of the beings residing in the Near Ethereal to rend and tear at the people behind the Greater Sanctuary for a moderate, though not too threatening, amount of damage/round. To make it a little more balancing, also, perhaps a yellow-text description that warns of the creatures on the edge of your vision, giving you a chance to break the spell by attacking something before you get mauled.
Not sure how feasible t his would be, but its a suggestion I thought up while drooling in line for the Bursar's office!