You're an established writer and given your science background and knowledge of history, you're more than qualified to give an opinion.

But the lead character "was" an admitted coward and was terrified when he learned he was chosen for the mission. He brings it up a few times in inner dialog during the trip. Overcoming shortcomings may not happen often real life, but it makes for good story telling.

The alien was the one of the most unique constructions of another life form I've come across. And one thing I've always enjoyed is the bridging of the language barrier with another species. It's treated in "Nor Crystal Tears" and movies like "Enemy Mine" and "Robison Crusoe on Mars" (if I remember right.) It's a battle where both sides are victorious in the end.

Be pessimistic if you like, you've earned it, but I have a hunch I'll thoroughly enjoy the movie, warts and all.