You can buy a good commercial deer hauler for $50 to $120 these days. My first deer hauler was a $42 dolly that had the bigger wheels. Got it at a Fleet store then painted it camo color. Use 2 straps to hold my deer down. It's sweet. For the sake of being easier, I'd have a buddy or two on standby, informing them of your hunting area and at some point, may need some last minute help to get a deer out of the woods. I'd jump at the opportunity to help someone get a deer out. From what you describe, these haulers may not work in much of the spots and just may have to be physically dragged out.(with help!)
For trail making, now that's fun! For me anyway. You can make a good trail with a hand held folding saw and a good pair of pruners. I have at least 3 of each. Our prickers here aren't that bad and are regional, so they are few and far between. Don't know how it will be making a trail through them. This is for a foot trail. For the more serious stuff, you can make the major trail in there for your 4-wheeler using a chainsaw and/or a weed-whacker with a circular type saw on it. Some just call these brush saws. Many people already own one.
When I read your title to the thread "Very inaccessible spot?", my first instinct was BIG bucks. LOL! From your observations and scouting, you found a high traffic area. Deer like safety and that's what they found in the back of that 70. I would do my cutting(4-wheeler) as soon as I could, then maybe make a foot trail or two, but nothing major. The deer will soon be using these as travel paths for themselves and by season, they won't think anything of them because they'll be use to it.
As for a ladder stand, you can haul it in 2 pieces. Those are the exact type places I would prefer a ladder stand. It should be safe there from theft, will most likely be there for a while, so it doesn't have to be moved much and it's nice to not have to haul a climber in there, then haul it out afterwards. Make yourself a harness to haul it with. I make mine so I can sling it over my shoulder, then carry it under my arm or to one side and the sling bares the most weight.
Keep us informed next year or whenever you take on this task. Be interesting to see what you decide.
Good luck,
iSnipe