1. You should have no problem finding a tent site during the middle of the week at this time of year. After school let's out will be a different story.
2. Both Elkmont and Cataloochee are great and you can not go wrong either way.
3. If the weather warms up a tad and stays that way you will probably be fine wet wading. That said, I haven't yet taken the plunge yet this year. I'm never in the water much. Last Saturday, in waders, I was a little warm while walking in but on Wednesday it was much more comfortable.
4. I do have a CC. You have nothing to worry about as far a security goes. You can't shoot the snakes or ticks.
5. Both of those options will require a pretty good hike and you will be skipping over a lot of really great water to get there.
Hope this helps. Feel free to email if you have any other questions.
jasonkelkins at yahoo dot com