When rounding out your workshop tools, consider adding two of the handiest tools used in shops of old-timers: a drawknife and a spokeshave. For the occasional job a drawknife can be used instead of the router for beveling work. It's fast and it can make fine cuts without any chatter marks. A spokeshave is like a plane with handles, making it easy to control the depth of cut for a perfect surface.
To store project plans, reference materials and magazine clippings, keep at least one two-drawer file cabinet in your workshop. You may be able to tuck them under existing workbenches. Or, if you will be building new workbenches, design them to accommodate the file-drawer cabinets.
Cords for small power tools like sanders and drills can get in the way when you work on a bench. One trick to keep them from interfering is to make up a chain of heavy rubber binders. Loop one end of the chain onto the cord about a foot behind the tool. Loop the other end over a cup hook screwed into the ceiling of your shop. When done, unhook from the cup hook and put the tool in storage.
If you are building a bench or table that won't be used for off-feed support for materials being processed, some general height recommendations include either 34-in. high, knuckle high, or hip-pocket high.
You want to do the right thing and include a first aid kit in your workshop. The question is, what should you keep in it? Here's a list of must haves: Regular and elastic bandages, antiseptic ointment, cotton swabs and balls, a tweezers, eye drops, elastic bandages with first-aid tape, gauze, a chemical cold pack, and a first aid information handbook. Also a list of emergency phone numbers either right near the phone or in the first-aid box cover itself.
Generally allow about 2-in. from the back of the tool to the wall, but be sure to leave space for any sawdust collection equipment you plan to install, including the ductwork and any attachments to it or to the tool.
Use caster sets to keep your major tools, even workbenches, portable. Wheeled tools and benches will allow you more flexibility, and will let you reposition for specific jobs like ripping long lumber or for taking advantage of natural daylight.
You can improve the visibility inside your workshop just by painting the walls and floors white. If your workshop is in the basement paint the sides of the window wells white too.
You can attach a length of soft copper tubing to extend the reach of a blow gun nozzle used with an air compressor. The extra length will allow you to clean out motors and interior machine parts without getting a face full of dust. The end of the tubing can be bent to reach around the back side of motors or into other hard-to-reach areas. Use a wet/dry vac along with the blow gun to help keep dust out of the shop.
Worn-out nylons can be used to hold tools on pegboard if you run out of pegboard hooks or have something bulky to hang up. Knot up one end, then feed the nylon through the back, and then loop it through appropriate holes for the tools you want to hang. The nylons will stretch nicely to fit various tool shapes and will actually hold the larger tools more securely than the older-style pegboard hooks. This trick works best if you are able to gain access to the back of the pegboard.