It would be great if the scheduling options could be expanded a little on the Tableau Server.
As a simple example - often times I'd like to schedule a workbook to update on "The first Tuesday of the month." This is not an option on Tableau Server as you either have to update it weekly on Tuesday or on a specific day (1,2,3,etc) of the Month. This one doesn't seem like it would be too much to add.
An additional example that might take a little more is: "The first Tuesday of the month - following the first Saturday of the month." This could be a little trickier to code but could easily be done by allowing a type in box: "The first Saturday of the Month" "+3"
These two things would give the Server Scheduling much more flexibility.
Others - feel free to add more scheduling ideas if you have them. These are the two that I've ran into that would really help.