He’s so dangerous, they tried to arrest him over the phone!
(He falls to pieces so quickly, people get injured by the shrapnel.)
OP posits that we’re on a serious mission. So for a traveling companion, I’d choose someone I can work with seriously and businesslike. That would be Legolas, I think.
OTOH, if I had to travel and work with Thranduil, things would not likely go well.
As the Eleventh Doctor said: “Never knowingly be serious.”
Ah, that explains a lot…those tiny little arms!