I've been loving this game, it's a refreshing change of pace from the usual games i see popping up. Might be something for way down the line, but i would love to see the option to make one of your custom NPC's to be a permanent companion/follower/lover and stay in the down after you manage to recruit them, maybe a similar system like how the npcs from town appear sitting down and you go and talk to them.
Maybe a bonding system where the player could choose to start bonding with one of the custom npcs and eventually they would spawn in the town or spawn in the player house. You could then go up to them, invite them inside and interact with them the same way you would with your custom npcs that spawn in one of the worlds.
I feel like any game that gives you the possibility of making a custom npc to interact with in the world like this game should plan for the possibility of allowing these custom characters to use the same system the base game npcs use when it comes to bonding or relationship building. Just as an example, i like the npcs from the base game, but when you can make Guilmon, Lucario, Renamon, Charizards and all these other hot characters, i would love to go and interact with them the same way you do with Sophia, Shale and every other base characters the developers have added into the game.
Right now it's barebones, you sit down and just talk. Say the developer plans to expand it later on so you can actually have dates with the base NPC's. Now you have a system with relationship building. What if you could use that system on your Lucario custom character? Or your Guilmon or Protogen and whoever else. Wouldn't that be awesome to do? Just an idea i wanted to share.