I see, that information is helpful. If you think it would be fun and engaging to play that character, then that's fine. There are some other characters engaged in teeth-clenched team work, so as long as he sticks with the others that's also fine. That does sort of render the weakness "doesn't work with others unless he has to" somewhat pointless, and would be better suited as a personality trait. Maybe some sort of weakness relevant to his fighting ability.
I do think that revival once per month is still pretty weak. For reference we have one character who can revive once every three minutes, although I probably won't permit something of that frequency again. You can choose something else if you like. By the way, if you intend for him to be able to use that crossbow, you should include crossbow bolts in his inventory.
Ok, so instead of that, would 'not very vocal about his opinions' work? As for my power, how about this. Perinu's Grace allows him to retreat away from any battle against anything, but only so far away. If enemies can predict where he will land, there is a short cooldown, maybe thirty seconds and during that time, if he was to even be hit by a pebble, he will die. That is to say, they can easily kill him.