Long post incoming, you are forewarned.
I would like to propose the following changes to skills:
1. Roll Lye Making and Potash Making into one skill - call it Ashery Worker.
Reasoning: Lye Making as it stands is currently the most completely useless skill in the game since the Ashery provides an option to make potash directly from ash. Even assuming that this option is removed at some point, that would then make the Ashery require two completely different skills to obtain anything useful out of it which is pointless complication and inefficiency.
EDIT: It has been brought to my attention that Soap Making still uses lye! Although I still have reservations about the ridiculous number of skills in Farming (see 3 below), it would seem Lye Making is not completely useless, even if it is entirely uneconomical.
2. Make Dyer a Crafting skill rather than a Farming skill.
Reasoning: Although the textile industry creates considerable interplay between Farming and Crafting, the position within your fort of each of the different steps (growing plants, processing them, dyeing the thread, weaving the cloth) may vary considerably. Your Dyer's Workshop is likely to be located near your Clothier, Loom, and cloth stockpiles whilst the Farmer's Workshop and Mill is much more likely to be near your farms and plant stockpiles. Having a burrow with blue dwarves dyeing thread, weaving it, and then making it into clothes is much more intuitive and efficient than having one or two brown dwarves running back and forth between your fields and your textile workshops.
3. Separate out Butchery, Tanning, Milking, and Cheese Making from Farming - make a new profession called Ranching.
Reasoning: Farming is one of the largest professions in the game, being the overarching category for a whopping 15 (!) skills. That's overwhelming and unintuitive, especially when these skills are spread out over a variety of buildings. By creating the Ranching profession, a number of infrequently used but still useful skills can be concentrated in one place. This would allow a mere one or two dwarves to handle all these skills in one small area rather than have the skills spread out amongst all your farmers. To further increase efficiency, put Milk Creature and Make Cheese in their own workshop - call it a Dairy Workshop - and place this new workshop in your ranching burrow.
4. Rather than move Dyeing to Crafting, move Dyeing, Weaving, and Clothier to a new profession called Textile Worker (or Tailor, etc.).
Reasoning: Similar to 3 above, the purpose here is to lessen the number of jobs in a profession to reduce clutter, as well as making more intuitive burrow / workshop groupings. I would actually greatly prefer this to 2 but it would definitely be more effort.