You use different foot positions when you run versus walk, and there is like NO overlap between the two, therefore if walking is a skill, running should be a skill too 
Running may or may not be sufficiently different from walking (pacing, different muscles used, etc.) to deserve a subskill, yes. Specific skills don't matter now, just whether we should have the option to specify or not.
Wood is wood. Stone is stone. Metal is metal. You could say that different masonry should be different, and different metalworkings and different glass working should all be hyper-specialized, but there's no point.
For those who care about quality there is. You don't need to, but it won't hinder you. And if it does, just set the 'gain skill' difficulty to 'cakewalk'.
In OUR reality people decided to specialize. In the dwarf fort-verse a wood worker is expected to be able to join/coop/frame/spin/whatever. You don't have coopers, you have a guy who works with wood in a variety of ways all day.
It's not a barrier to entry, it's a barrier to become a one-person factory of everything. And as a matter of fact, in my fortresses I
do have dedicated carpentry workshops for bins and barrels. You should still able to say: I allow this guy to do all kinds of woodworking with one keypress, instead of scrolling to a list with 543 skills, but that's an interface matter. The subskills idea allows the ones who care to specialize without having coopers that are totally incompetent at other woodworking skills, while other players won't even notice.
The last thing we need is more specialized skills. Bowmaking should be removed as is. Subskills might be more viable
Subskills allow experience to benefit general skills, while still rewarding specialization. Fletcher is a relatively common name, just because making arrows was a common fulltime occupation. Hell, there even were specialized smiths that made arrowheads.
Making cabinets out of stone and metal are nothing like making them out of wood. I have to object to there being a synergy between different materials
Regardless of the material you make goblets/mugs out of, you need to know what is a good shape and size for the handle, what kind of patterns are popular, and that making the foot spherical is a Bad Idea.
It's best to define skills by the product part, so we'd have a raw with a list of procedures. As subskills after it would come a percentage for the material and a percentage for the product.
eg. [skill:cooping][material:40][product:10]
eg. [skill:forging][subskill:heat_metal][subskill:hammer_metal][subskill:quench_metal][material:50][product:10]
In the products raw there could be a list of objects and services, with a list of the required and optional materials and procedures.
eg. [product:barrel][procedure:cooping:wood_any:1][forging:metal_any:1]
eg. [product:pipe][procedure:cooping:wood_any:1][procedure:forging:metal_any:1]
... meaning a barrel is made by applying the skill cooping to wood, producing a barrel. The skill number used to determine the result consists out of 50% of the cooping skill, 40% of the material skill and 10% of the barrel skill. Experience gained is divided in the same proportions.
The same could be done to make a pipe by cooping. That pipe could also be forged. It's possible to subdivide that skill to represent that a given procedure takes more time and effort than others (eg. forging consists out of heating the metal, hammering, etc., all taking place in the workshop), but that kind of detail probably won't be in the vanilla version.