Harry Potter...

The plot was drastically cut down; Beorn and Tom Bombadil were simply removed, even though both characters are charming and memorable.

A necessary sacrifice to fit the already long film into the allotted screen time, and these characters aren't essential anyway. ha_ha_I_am_tom_bombadil_welcome_to_my_forest_of_faggotry.jpg x)
And the doves were mentioned in the original book; what do additions have to do with it?

Arwen, who has completely different facial features that don't suit elves at all.

I knew something like this would be written as soon as I saw it. But what else could you expect from an inferior race making a film about Noble Elves? They can't even find suitable actors!

a glamorous pretty boy instead of Legolas

Didn't you realize what you were getting into when you started watching a film featuring elves?
Also, I don't know where you saw Armenians.
Anyways, as a film adaptation, it's good, much, much better than Potter, which is why it's a good example.

Also, I don't know any sweet boy who could lead more than one person.

Well, now you do!! It's amazing that you thought Alexander was a stern general all this time. The aforementioned glamorous pretty-boy elf is even "tougher and less pretty" than the Mediterranean boy.