If you want 5 traders max in whatever world you create, all different traders too, Jen, Hugh, Joel, Bob, Rekt, then just set the "City Trader" option to "One in Every City", while setting the "Traders" option to "None". Every time I load up a world like that and check, I have 5 different traders, distributed around the map. Adds a more Navezgane feeling to exploration, where you won't run into 2 trader Jens in the same world.
My advice, Damocles, is try to add an option for the player to spawn within 1km of a random trader; Within 1km of his or her preferred trader, if you're feeling ambitious. I typically have to walk 2-6 KM to reach the nearest trader with these settings, so it would be really helpful if you implemented an option to allow the player to spawn close to a random trader. I'd use the TPPOI command to teleport to one, but that disables achievements =( This mod is nearly perfect and I'm tremendously grateful for all the time and effort you've put into it. I believe following through with this suggestion will make it truly perfect, at least to my standards of gameplay. Playing in a world without Traders at all is AMAZING with Nitrogen, really opens up more of the world to the player. Having more diverse POI's to search adds to longevity and reduces the finite nature of vanilla worlds, where items are concerned.