I suggest adding a few greater diseases to the module. Greater diseases would require you to be a high level rot/disease focused PC and would be applied to a subdued character directly only with no chance of spreading. If there is interest I'm sure we could write up a few balanced scary/flavorful diseases rather easily.
These diseases would require the implementation of a spell called 'Remove Greater Disease', akin to Remove Curse and Restoration.
Some diseases if not cured in a decent amount of time may cause the character to receive interestingly awful effects like hardened skin, boils, loss of limb, etc. Allowing a renown rot PC to leave their mark on the server in a sense.
I am in love with anything revolving around poisons and disease. Allowing disease to have an effect on the server is wonderful.