I too think that Manato isn't talking his mind with the party. And those praises he always tells made it obvious while the group is still so shocked for the new world enviroment that don't think it twice to take for granted his words without see the backside of it. Still i don't see ill intention on Manato either, what i see is he putting a front of positive guy to balance the party's moral while having his own issues.
Naaah, youre wrong. He is way too perfect he has no ill intention. Just a leader of newbees.
It might be just my paranoia born from reading too much fiction but I can't help thinking that there must be something fishy in that Manato guy. Nobody is that perfect. ( ̄へ ̄)