Is there more to all the explorable areas?

I noticed that this game's world is absolutely huge, but alot of the areas don't seem to really have anything going on in them! I have been doing a bit of exploring lately, and some of the areas in this game look extraordinary visually (Two of my favorites that I've been to so far are Kessek Peaks with the flying tower and another area east of the great northern wall, with a giant crystal surrounded by water in the middle of the map.) However alot of these areas don't really seem to have much that you can actually interact with (aka, they may have like 1 quest for 500xp or something and that seems to be it for the whole zone...aside from the obvious hordes of random monsters!). Are there other things in all of these open areas, or are they mostly there to look pretty and connect the cities/mission zones?

Many areas in Prophecies are like that. As you have found already there are a bunch of areas that essentially just join significant areas together or flesh out the map. Factions, Nightfall, and EotN are not like this though. There are much fewer areas and they are all more densely packed with quests and such.

PS: You'll get a lot more use out of the Krytan areas later when you get to a series of quests called 'War in Kryta'.

There are Zaishen Bounties that require you to assassinate (maybe I've been playing too much Assassins Creed ) bosses in some areas, Kessex Peak being one. Also theres a tough if your new quest there and after that an even harder one.

You'll also have to kill every enemy in those areas if you want the Legendary Vanquisher title once/if/when? You unlock Hard Mode.

I think it's good to have places that are off the beaten track, gives you places to explore instead of the story just saying, ok just go here do this then move on.

In hard mode, these areas during a vanquish have more than enough to do and all of it is trying to do you! Little critters become a challenge when they are level 24. WoW also had at one time big areas with not much going on in them. Revised WoW uses more of the spare maps. Factions and Nightfall have much more going on in the explorables. As does Eye of the North. Prophecies was originally intended to be a more complex game than was wanted in the final conception. So there are areas that appear to just be there for no good reason.

Don't forget about chests :3