1. The reason why there was no 3rd person view is because this isn't a Bethesda game. It is actually developed by the great id Software, and is merely being published by Bethesda. Long story short, outside of vehicles there will be no 3rd person gameplay in Rage.
2. I personally haven't gotten my mitts on the game just yet, but reviews and player accounts seem to indicate that the campaign is around 20-25 hours long. Doing the math on Let's Plays also point to this.
3. Not sure how to answer, seeing as it isn't a question. But the actual RPG elements seem to be fairly light, so it is more of a shooter where you can build things and grab loot.
4. Not sure
Sorry, but my answers may or may not be entirely reliable, seeing as I am about to get Rage in the coming days. But I hope this helps, because the Rage forums are dead, so it may be a day or two until you get another answer. But I would maybe watch some videos on it and play through the demo a few more times.
On my last playthrough of the demo, before I went to go into the well I had $1000. It is a long process, but you can find a Vault Tec Bobblehead in the mayor's office, which sells for $150 dollars if memory serves right. After that, find all the cards scattered around town (they are glowing red tins, which are commonly found on the ground) and head to the Second Chance Tavern. In the back corner of the room you can play this entertaining card game that is quite easy, being mostly skill based. The mutant minigame on the street is also great for making some money. So after that, you can head to the shop and buy any supplies you may need, including an Authority Assault Rifle (the one featured in the trailers) and some interesting ammo types. There is even a recipe to make Fat Mommas, which are twice as powerful as Fat Boys.
Hoped I could help.
