2) What are the advantages of getting Human status over the network? Apart for an extra flip, I see only that he can miss the short session, but he can NOT miss the long session. This is kind of weird because if you are not at the PC at the time the validation starts, you most likely not be around for a while, so you will miss Long session too. I don't see this an advantage.
5) Will be the additional flips made by the Validated/Humans rewarded?
ad 2.
1- stake protection
2- extra flip
3- extra invitation (after another fork)
This rule is about failing validation not missing it. So you can get <50% and still do not lose stake. Both verified and human accounts can miss whole validation twice without punishment other than exclude from mining.
You Validated/Human than Suspended than Zombie than killed.
ad 5.
Yes and they are not mandatory thus. The only thing that is a pain is that there are still only 9 pairs of keywords. Way to less to create 5 high-quality flips.