Gary Sweet was not what I was expecting, but he was good in the role. I didn't much care for the accent, but I thought it worked well enough and got used to it a few words in. His appearance was fine with me. I hadn't read VDT in more than a year so that my preconceptions were fuzzy. He looked and sounded great.
My one problem was when he turned to Edmund and said (pretty much), "Excuse me. Who died and made you king of Narnia??"
...
...
I wanted Ed to look at him and say, "Aslan?"
I just really wanted Ed to put Drinian in his place, or at least Caspian should have put him in his place. Grrrrr... Drinian was right, but it was badly done... Very badly done and highly disrespectful.
I always assumed that Drinian was a ship's captain from Achenland who was sent over to Narnia as part of a sort peace thing after Cas was made king. Anyhow, that's what I thought of him in the book. Especially as there were no captains in Narnia until Caspian became king. So if he had any prior experience he sort of had to be foreign. In the movie it was the same thing, but add his fair complexion to the mix I really assumed he was foreign.
With that being said, I really liked movie-Drinian and gave him a place in my book next to the awesome characters.