Thanks for the link.
I see on the basis of your pics why 2800 was recommended as your balding is more progressed.
For question 4) on the basis of your pics, I'd suggest you take a look at spreadlock's photos here
. Perhaps you can achieve something like this "epic comb-over". If not then I guess a military cut might be your only option.
As for hats, I asked Dr Feller and Spex about this yesterday and they said caps/hats were absolutely fine to use. I don't think it would be a good idea to use them for the first few weeks while the scars are healing etc. but some loose fitting caps after then would be helpful.
You might want to look at the forums here
for advice specific to hair transplants, by fellow patients, doctors and veterans.
Edit: looks like my link has been blocked. I do hate that; so unnecessary. Just Google "hair + transplant + network" and you'll find it.