Allow multiple types of items to be sacrificed at a time.
Just like when selling more than one thing.
Editing for clarity:
Right now, afaik, there is no way to sacrifice more than one stack at a time, which can make saccing quite time consuming. If I have multiple stacks to sacrifice (which is almost always the case) right now I have to hit shift-o, hunt through inventory for one, confirm, get sac message, hit shift-o, hunt through inventory for two, confirm, get sac message, hit shift-o, hunt through inventory for three, etc.
Now imagine if you have 10-20 stacks you want to sac. It takes forever, and is one more reason why inventory size is out of control, it's more trouble to sac the items than to just carry them around. If you are playing a hated race (like dark elf) you are wasting them if you sell them.
Just like when dropping items to sell, you should be able to open the sac menu once select more than one stack and then confirm the sacrifice. It would save a ton of time and reduce inventory size. It doesn't look like ':o' is being used, so maybe that would work as a command.