When you post such imponderables on the internet (and it
was your first OP question), any number of responses you get will likely be from somebody selling something. They will all be impassioned.
My perspective on Roatan's diving comes from many dives along all of the shores. There is something good to see on either side, no particular one is better than the other. Most local "experts" have had only a small sampling of diving "on the other side" from where they habituate.
South Side addicts may often judge the entire North side by their special trip to the North to dive the Aguilla Wreck. North Side regulars have a number of dives at Mary's Place and judge their experience accordingly. Both limited perspectives are very faulty.
Divers of a certain ability level will find their excitement in seeing their first Lobster, Crab or Shark. At early stages in diving, many divers need larger familiar named critters, or dramatic reef structure and "wrecks".
It is a common thing for many divers to completely "not see" even large creatures that are lurking in plain sight on a wreck or a dramatic wall. We are so overwhelmed with the obvious that we can't see the details. This is no mistake, it is a demonstration of natural camouflaging instincts of these animals. We humans are really crappy hunters~ we have to learn over time.
As you progress, you will find these fairly obvious larger critters & objects somewhat repetitive, and you will be looking for something else, you will begin to see the "trees within the forest". Your eyes will sharpen, your tastes and needs will change.
"Micro creatures and soft Corals" as mentioned previously will then become the next holy grail.
Your need for snorkeling does throw an interesting curve into it, especially on Roatan. The availability and access while on Roatan runs from 1>10, but not much in the middle. The resorts and locales you have so far specified
aren't at the high end of that scale.
You ask many questions, but unfortunately offer a limited perspective of your described needs. On question you ask..."Is it worth driving to the South side to dive" opens up an entire different avenue of the thread. I would start with this: drive nowhere on Roatan, always hire a driver. Search here on ScubaBoard in this forum for the collective wisdom that supports that advisory. Then go into the remainder of your query. In a nutshell: it is much easier to "dive-op hop" around the West End, but that will not offer a solution to your "other side" curiosity.
NCChuck's appraisal of reef health is fairly accurate, but the real causation is simply not the volume of visitors. It relates more to estate development and highly localized micro-currents.
NCChuck also offers you a very interesting & viable solution to your needs with Reef House Resort. You should look into it. Start right here:
http://s221.photobucket.com/albums/dd106/Doc_Adelman/Reef House Resort Roatan/
Roatan is many things to many people, all depending upon the breadth of their experience.

:sblogo:
It works.