Well first off, Good Luck and at least it's a good start for the conversation but this should be done right if it's ever done not just small changes and clones and definately not something that will need extra or different attention.
I like the Fel rule set concept but I believe there has to be safe areas. I think the areas should be further divided into dangerous Non PvP and extremely dangerous PvP.
This way, within the PvP areas death can happen to anyone, so that the risk is greatest for the murderer.
I would use Guard Zones, NPCs to help control areas and protect players. For example: Mines that have guards in them and then mines with just workers in them to mines that are empty with possible spawns, traps and of course PKs.
So, i'm just saying, PKs would still have the smallest area but they would not have to worry about groups of NPCs or Guards or both but then those areas would be just as deadly to them. I would even set traveling NPCs who would search for Reds and kill them, so that they would too, also feel what it is like to be hunted, what it means to lose.
In a world like that you also need a balance for a reason to live. You can't just change the rules and expect the game to be new. You have to change the game, increase the land mass to push people away from each other rather than one main road for example, there would be two but create those interesting draw points along each road.
If there's no change, than the numbers would stay low, in my opinion. Curiousity is a huge part in setting up places on the surfaces, you could have completely random spawns. Like an Evil Mage Tower with Evil Mages and unique drops, perhaps special potions that give an extra cap to your stats and last for a few days.
And then the next day the tower is gone and it's replaced with a strange cave and eventually the landmass becomes a living, breathing area, full of change and endless possibilities. This should be the main reason for a change in creating a new landmass, so that you could optomize what you could not before because of stagnent objects. For example: Again, roads. Roads could be built by the number of people who use a path, meaning they would not exist at all unless people travel in a direction that created a path but unless this is planned ahead of time, roads would simply just either be stagnent or end up going all over and around different houses.
Also, if they create a shard that's new, I think there should be huge incentive to go to it. Like, think about all of the characters you could have on all of the shards. Think about all of the bank space, boat space. Wouldn't it make more sense to just play on just one shard and be able to have a reasonable 15 characters. Wouldn't it be better for the player, to be able to have ship hold with 500 items rather than have 500 boats?
I think organizing the player to focus in one area brings them together with other players because other shards basically build walls between the players. For example: 5 players each play on a different shard. These 5 players play the same multi player game but will never see each other.
So, because of that I think it should be important or a priority to bring people together and I would lock out the other shards so you would only be able to play on that one shard. So, you could change your main shard to the new shard but then you would not be able to play on other shards. For example: Any new player would begin on the new shard. Old players could make a choice to move to the new shard and would be given many incentives, rule change is not enough.