The problem with some of these labors isn't so much with what the labor puts out, but rather with what the labor needs. Most liquids in Dwarf Fortress can be kept in barrels and pots - for some reason, jugs and buckets are the primary holding source for milk and honey, rather than a tool used to move milk/honey from the source to a barrel/pot. In addition, bees and animals produce a small amount of honey and milk, respectively, and need a large period of time to produce enough material for a harvest, and keeping large amounts of either requires large amounts of buckets and jugs. If you only needed one bucket per farmer's workshop, for instance, because the milk is moved from the bucket into a proper barrel automatically, the cheesemaking industry becomes less taxing on necessary materials and becomes more productive due to the cheesemaker now having more milk to work with at a time. Modding in plant cheese alleviates the problems with relying solely on animal cheeses with regards to harvest size in relation to harvest times, but the bucket issue is still present. In addition, overshadowing the cheesemaking industry is just how lucrative prepared meals are despite just how much easier it is to get the raw materials (which is pretty much anything edible). Even meals made with nothing but plump helmet spawn will overshadow anything a cheesemaker can produce. When the world's economy is finished, this might change, but for now that's the major problem with the labor.
Waxworking can be expanded, yes. Wax crafts in and of themselves aren't completely useless, at least not much more than stone or bone crafts are, but making wax candles (which can be placed in a room for a happy thought) could be a good addition. Wax working might also be a labor to look at for when dwarves become literate - wax seals are a good way of proving a document is official, for instance, and globs of dyed wax could become a valuable export commodity.
Animal Dissectors turning animal corpses into statues is also a good idea. The size of the creature and the inherent danger of it should have a direct effect on the value of the statue, I think. A stuffed dragon would be much more valuable than a stuffed frog, after all. When dwarves become literate, animal dissectors could function as an opposite to tanners, turning fresh rawhide into vellum rather than tanned leather.
When wood as a material is allowed to be pressable, pressing out oils and perfumes for use in other industries would be a great boost to the pressing labor. And, like wax working, pressing would become even more useful when dwarves become literate. Pressing reeds to make reed paper, for instance.
Soapmaking... I'm not sure if there's really anything to do to make it more important: other than make animals require soap to clean their wounds instead of only dwarves, that is. As of now, a fort with dwarves suffering injuries often has a great need for soapmakers. If the issue is the need for tallow, then modding in plants that can be pressed to produce soaping oil fixes that.
For the traits that ElfCollaborator mentioned, there'd be no need for those to get labors of their own. Creativity has an effect on Engraving, correct? When dwarves become literate, writing ability will likely have the same effect. When musical instruments are finally playable in Dwarf Fortress, musical ability will finally have an effect as well. Some of these traits could also be applied to alchemy if that should ever arrive in vanilla DF.