I think you can go simpler, especially to start. Expand and break our subforums as volume of posts drives it:
1. General topics
2. Weld processes - MIG, TIG, Stick, Oxy-fuel
3. Fabrication - design, building, forming, joining, machining
4. Tools & Shops - equipment, setups, shop photos, etc
5. Projects & Pictures
6. Safety
Brand specific
7. Miller
8. Lincoln
9. Hobart
10. Others (or add more individual ones as you see fit)
11. Off-Topic ( ya always gotta have one or the regular forums descend into chaos...)
This isn't terribly far off what WW has right now, but then I think their structure is pretty simple and solid overall.
My 2 cents..
Edit - Oh yeah #12 - For sale/services offered.