I'd say yall don't have much to lose in opening a new SMP server.
For 2 reasons
I've been away from this community for along time, but from a outsiders perspective RoF is already pretty dead. Personally never liked it, not even in classic. The gamemode itself was not appealing to me as it required little ability... Not going to take away users from a server that never really has users.
AoD and Create has their core group thats still active. Opening a new smp server shouldn't really have an effect on AoD or Create, but it may help bring in a new influx of new users. That's the main issue i see here. There is no churn rate of users because there is hardly an influx of new users...
I'd bring back SMP but I rather see something akin to ole primordia a fantasy RPG setting
Could use LegendQuest as a backbone plugin
https://www.spigotmc.org/resources/legendquest-rpg.2120/
Highly customize-able rpg. dependent on spigot.
Can work with towny factions etc
Or we could do something more smp in a fallout/ walking dead world
Could use Crackshot as a backbone plugin
http://www.curse.com/bukkit-plugins/minecraft/crackshot
Another highly customize-able plugin that allows to easily add custom guns and make up recipes.
Then use this mod
http://dev.bukkit.org/bukkit-plugins/cityworld/
For map generation to be lazy. It'll just make the world a giant endless cityscape.
~~ You can customize buildings too with world edit. Supports generation of 64x64 with unlimited height. (4 chunks)
Throw down some custom zombie spawners and were walking with the dead people!
If leaning towards a more heavily modded primordia smp style, I'd do a set map. (Happy to help make it too)
Either way i'd say we'd want something like this for ultimate retention of users
~Preset factions, with factions within factions. I mean having the ability to create factions is nice, but it can really divide people up and the next thing you know you have 20 factions with 2 people each that never really play. Common cause to unite people and keep them in the loop.
~Protected safe bases/areas for each faction. perhaps inaccessible islands removed from main continent.
~Pve area, mob arena where you can team up with friends and level up
~Open pvp wasteland with key strategic locations and spawning loot.
More importantly this would have to be driven by player events and good gms. Good events drives activity.
~Biweekly tournament type events that flipflop each weekend at peak times.
~~example: Tournament o Glory
~~5v5 2v2 and 1v1's where factions send out teams for glory.
~~Winners get unique items, bonuses for their factions and get their names etched down.
Then the other week there might be a PVE invasion(GM led) or some other kind of quest etc. Or mob arena contest etc.
Just a suggestion. Here to help though. I can certainly throw a large map together for this. Customize the plugins up a bit too.