Thinking about swampy areas again, here’s a description of an area I’d have a lot of fun playing in.
The area starts with a small fishing village which is at the end of the coastal highway running between steep cliffs and the sea from the previous interesting region in the South. The village is build on a rocky promontory which also provides a small harbour, but past the village on the other site of the rocks is a swampy delta which needs to be crossed to make it to the next large city. The cliffs move inland around the back of the swamp, eventually leading to a large waterfall which feeds the swamp, then continuing around the back of the swamp toward, and after some time the city is on the more pleasant land at the top of the cliffs.
The highway continues through the village and across the swamp - it’s well built up and maintained, and easy to traverse even for large merchant caravans arriving from the south. There are a few bridges over major waterways, and maybe an outpost somewhere for a bit of flavour. After the swamp ends, the highway actually gets worse as it reaches the foot of the cliff leading to the city and there are a series of steep switchbacks to climb the cliff.
The player is obviously trying to reach the city for some plot reason, and of course there has been some kind of cataclysm which means the world is full of monsters now.
The city is under siege from the evil army, but most of the sieging is going on at the main gates leading out the other side of the city onto the plains on top of the cliffs. There is a small but sufficient evil force which has been sent to block the highway through the swamp, although assaulting the city up the cliff road would be suicide for them. There are also assorted wild crawlies; crocodiles, snakes, giant leeches or whatever else lives in swamps. There are also some kind of flying nasties living in the cliffs.
The swamp is passable, but unpleasant, possibly with random light poisoning effects or something else that would be trivial for a healing type player to shake off, but would be irritating (not really dangerous) for those without easy healing.
Now, the player’s primary goal is just to reach the city. This can be achieved through either muscling along the highway through the evil army unit, going off-piste through the swamps with sporadic poisonous critters and occasional patrols to be avoided, or taking a cliff path and dealing with the nimble flying beasties. Some of these options will be easier for different play styles, which should help replayability with different classes. Also, the first objective is just to pass through the area so actually killing the baddies is less important than rushing or shielding your way through if the baddies won’t pursue you.
For more value there will be additional quests to actually clear the three routes rather than just getting yourself through. Open trade to the city again, clear the mountain path, and maybe find something in the swamp. This will be more difficult than just getting through, and should be tied to some other major quest system like organising resistance to the evil army (complete 5 of 8 ‘help settlements’ quests to advance), and will require coming back at a higher level.
Then, once the routes have actually been cleared you can change the enemy spawning profile of the region to a ‘scattered resistance’ model where you can walk down the highway without being molested by rats every five seconds, but you will still encounter SCATTERED, tougher remnants of the evil army which you can either fight and will be challenging to your new higher level, or avoid if you don’t actually want to participate in this region at the moment.
All in all, I think the feature I would like most is to have different models for ‘initial spawn’ and ‘respawn’ to change the character of areas you’ve been to before, and to make conflicts optional once you’ve thoroughly trounced them once.