One option, which I am surprised is not used in 4E (where you can level up critters easily and create a diverse set of encounters based on 101 kobold variations) is to have fewer types of monsters with more depth.
Do you know the type of FURY that would erupt from D&D players if WotC decided to exclude a lot of monsters that were in earlier editions?
There was mass anger because they chose to put FROST GIANTS in MM2 instead of the first one.
Middle Earth gets away with it because they didn't HAVE four dozen different monstrous humanoids gathered from 3 previous editions of D&D, in addition to all the
other monsters acquired over the editions people want.
I suspect that the 4E trade-off is towards breadth -- in which case you need to find a lot of new names that are easy to remember and difficult to get confused. I agree that the naming convention is sup-optimal but choices are limited if you want 100's of monsters, dozens of powers and a lot of outer planes (that will be hard to confuse).
But I think you're on to something. However, you're saying something about them having to be remembered.
No, I think they have to come up with different names so they aren't repeating the same name over and over again.
For instance, each monster group typically has a Skirmisher, a Brute, a Controller, an Artillery, a Lurker and a Soldier. Some have more some have less.
Now, you need a NEW name for each skirmisher. Because "Orc Hunter" and "Kobold Hunter" and "Goblin Hunter" and "Gnome Hunter" is going to make the fans hunt down the guy calling them "hunters" and shoot him in the face. So you need a
new compound for each skirmisher/lurker on the same theme.