Whoa, thanks for all the great responses everyone. Lot of thoughts here. A bit more on my background. I do have some basic medical training slightly more than is required for Florida First Responders. My degree was also in Aerospace Engineering and I'm pretty good at working my way through problems as the present themselves. I have more history of building things from scratch than the average engineer, but not as much experience as a mechanic.
First off, I don't have a gun. I don't have any training with firearms and I've only fired one once in my life so I just wouldn't feel safe having something I'm not fully trained on using. I do have more knives than the average bear, but not a gun. I can definitely see the advantage though and it's something I will keep in mind, but I would want to take some classes or something first to make sure I'm educated on how to use it in all situations.
Tires
I'm glad to hear that I am on the right train of thought about tires. I had a scare last week just around town when I found a 4 inch nail sticking out of one and realized I didn't have a proper spare. Luckily I swapped out the stock highway tires for 245/65R17 Cooper AT3's and the nail didn't do any damage, didn't even puncture the tire. I've got about 7,000 miles on them and they have been great on the highway and sand here in Florida.
Jack
I don't have a highlift jack. There's no place to use it on the Subaru anyway. I do have one of these from when I had my Hummer and it works great. It's a combo bottle jack and jack stand. It provides a very sturdy base for any work you need to do on the road.
http://www.amazon.com/Powerbuilt-640912-All-In-One-3-Ton-Bottle/dp/B003ULZGFU
Communication
I've got my cell phone and a portable battery for it. I'm also looking at a small solar panel to trickle charge it if needed. I don't have my HAM license but it is something I have been telling myself for years that I wanted to get. This might finally be the push to just go take the test. I do miss my CB a ton, I've got to look at getting a small unit again. That thing was better than a radar detector on highways.
I looked at the SPOT devices and other PLB's. I really want a Delorme InReach. The 2 way communication aspect is a big deal. I might even be able to get my parents to split the cost with me just for their peace of mind. I'm also going to be blogging as much of this trip as possible so being able to post to Twitter from anywhere is a huge bonus.
Recovery
I have no idea how to use a recovery strap on this Subaru. Everything is plastic. I have the threaded eye bolt that Subaru provides but I highly doubt it's strength in a situation where I'm severely stuck. It's 5/8 in diameter at the threads and 3/4 for the rest of the bolt. It might work if I am just stuck in snow or having traction issues, but it I find myself in mud I don't think it will hold up to a recovery strap.
Onto to traction mats. I have looked at the Treds, the new Tred Pros look very nice but they won't be around until April. All of the Tred's products seem to have very large lugs on them. I read the very long thread about them in the recovery section and someone over there had issues with the AT3's not grabbing the larger lugs on the Treds. I'm leaning toward the Maxtrax, I just will have to see where I have room for them in my budget.
Also work Gloves...oh yes. I need a new pair. Thanks for the code, I saw it in Overland Journal and will probably use it when I buy a pair. Those black nitrile gloves are also amazing. I highly recommend them to any of my friends working on cars.
Medical
I need to brush up on my training here. I did a First Responders course back in college but that was 6 years ago now. It was 85 hours of First Aid training and drills. I would be really interested in taking a wilderness first responder of wilderness first aid course. I'm going to look into that.
Sleeping
Well that's the million dollar question at the moment. First I planned on building a sleeping platfrom, but I'm realizing that I need more room for storage than I thought. In addition to the offroad gear, food and water I'm also packing a bunch on camera and video equipment. I want to film my whole trip as much as I can and all of that takes up space. So I was looking at a RTT, but I'm thinking for the cost of that I could buy all my safety gear (hence this thread) and get on the road and have adventures sooner than if I had spent the money on the tent. Right now I have a 1 person backpacking tent that I've had since high school. It works but it's too small for me, I'm hitting my head on one end and feet on the other. It's not a long term solution. I'm probably going to spend upwards of 50 nights in a tent next year and probably more. The RTT investment would be well worth it for quality of sleep and piece of mind but again, just comes down to cost.
Fuel
Ok, question time again.
Is there any safe way to carry fuel inside a car? I've always been told keep it outside at all costs which would mean a roof basket of some sort since there's no other mounting place on the Subaru.
So here is what I'm thinking to buy:
Full Size Spare Tire and Wheel
Tire Patch Kit
Compressor
Tire Slime
First Aid Kit
Roadside Triangles/Flares
Maxtrax or Treds (1 set of 2)
Fuel Container
Water Container
CB Radio
Gloves
Paper Maps of states
Recovery Strap
Tool Roll
After that I'm going to have to budget out the following:
Delorme InReach PLB
Tent or Cot
Offroad Lights
Camp Lights (Floods)
As far as things I already own that I will bring with:
Bottle Jack/Stand combo
First Aid Kit
Flashlight
Matches/Firesteel/Zippo
Gloves
Bug-Out-Bag with Food/Water (Energy bars are a great idea, high calories, low space.)
Tools, breaker bar, torque wrench, ratchets, razor blades
Did I miss anything. This is just the things I consider safety issues. I'll toss up a build thread about the rest of the things I'm bringing later but I think this is a pretty well rounded list for things to keep me alive and return safely.