My thoughts.
You didn’t say where you are located or if you are already going to do this, but insulate the bee-geez-us out of the building, inc. quality windows and doors! The more comfortable you make the shop, the more time you will spend there.
Sounds like you have a good idea as to what you want you want to do. IMO, you can get by on the tools that you now have.
As Bill H suggested, install a good dust collection cyclone. I have one and it is worth every paid I paid Oneida for it. Same with Bill’s advice as to tool lay out. When I did my shop (30x36 detached building, wood shop is 24x30), I made a large scale drawing of the shop area and tools on butcher paper. I then moved the tools around until I was comfortable with the layout. I found this visually more user friendly than the computer screen.
MY tools are laid out so I can see anyone who comes in the roll up garage door or side access door while I am using the power tools or at the work bench. A much safer way to work.
Also have magntic starters (AKA switches) on my power tools. Once was running the router table and there was power faillure. Before I could turn it off, the power came back on. Good thing I had not let go of the work. Lee Valley has a GFCI that must be re-set after a power failure
http://www.leevalley.com/US/wood/pag...53&cat=1,42207
WoodCraft has a similar safety device that plus into a well receptacle or extension cord.
http://www.woodcraft.com/Product/208...fessional.aspx
Have a good first aid kit handy.
Good lightning: as we get older and on dark days, more light is needed. Have the lights wired so the whole shop doesn’t need to be lit.
Tools and shops naturally “attract” thieves. Think about a shop alarm system and a phone line. The windows in my shop are high to keep out “inquisitive eyes“. Plus the roll-up insulated garage door has no windows. Having windows up high leaves more useable space beneath.
As for tool upgrades or future purchases, I always recommend a good quality cabinet saw. And a good 12” planer plus a long bed 8” jointer are well worth the money. The De Walt 735 planer seems to be a very popular and well-made machine. Might be best to hold off on buying more tools until you really get started and then you’ll soon find out what you want and what you really need is often two different things.
A number of woodworkers often skimp on quality lay out tools. An accurate and robust square while having a stout price will last a lifetime and have readable scales. A good marking knife and/or marking gauge leave a clean and sharp line.
Router bits -- doesn’t make sense to buy these “dream router bit starting out kits” as I’ve seen far too many of these dubious quality kits sit in a drawer with only very few of the bits ever utilized. Buy good bits as you need them. As for straight bits, machine shop end-mills will work just fine.
As for air, I have cast iron oil 25 gal. unit from Grainger which runs the pneumatic nailers. ‘Nevva’ felt that this unit was underpowered for what I need. Some shops have these humungous air compressors, but are they really needed? Unless you are doing air sanding, drilling, spraying, grinding, etc., IMO they are overkill.
When I spray, I utilize water based and a HVLP turbine/sprayer. “E-zee” clean up and presents the ability to apply several coats in one day. When the weather is nice or the shop temperature turned up high, I can apply two coats of water based sanding sealer and three water based coats of poly in one day. Plus with water based products, chances of a shop fire are greatly reduced.