No staking rewards means people are going to set their reservebalance to maximum and stop staking, which leaves your network vulnerable to attack. I wouldn't recommend it.
yes. And I just said the incentive is if you wish to move from A to B then stake;
else the network does not move for 30-90 minutes.
BONUS is that you gain all fees in that window of time.
As popular demand picks up then that spans can shrink to to 3-9 seconds and as it wanes return to 30-90 minutes.