Hi, with the exception of mayo I have used all the other things at least once.
Beans and spaghetti are good when poured inside your clothes, but tend to all drop off with little effect if put on the outside of clothes. The juice stains pale coloured clothes, the smell doesn't linger too much but don't try to wash them down the plug-hole or they will block the drain.
Gravy feels slimy, smell lingers a bit and it tends to leave a fatty deposit that is a pain to get rid of, I used lots of Fairy liquid to try to get rid of it last time I used gravy, I would be wary of using it again as the cleanup outweighs the good feeling, and it will stain pale colured fabrics (including towels-oops

)
Soup is strange and I have had mixed results with various types in the past, remember the tomato based ones will stain, and I have stained my skin with tomato soup in the past, oxtail and similar is like gravy (see above), mushroom was just a slimy wierd substance, last time I used minestrone which was good, although again it contains gravy-like qualities.
I have only used ketchup and sauces when I was sploshing with other foods so I can't really say what they were like on their own, but brown sauce has a strong lingering smell.
Mashed Potato is also good if you make it a bit runny, although the starch in it can make it set hard if you are not careful.
Much depends on if you want your costume to survive, or if you want to destroy it completely.
I very rarely put mess in my hair, as I can't take the chance of not getting rid of it, however I have done in the past and used eggs, yoghurt and other sweet stuff that washes out with mild soap easily.
I have included a picture of myself having a really fun session with practically everything on your savoury list with the exception of mayo, I spent about 20 mins getting messy, 10 mins cutting and shredding the outfit I was wearing, and 3 hours cleaning the mess up and trying to get rid of the smell.
However I don't want to put you off, just make you aware of what may happen when you use these things.

- savourysplosh.JPG (25.71 KiB) Viewed 3288 times
Have fun, and don't forget to post us some pictures!!
