The home system should be something that helps the character.
GW2 implemented a home system where you can get resources to manufacture or sell. What's bad: you can only do it once a day and it's extremely monotonous and boring, there's nothing special extra to do other than just collecting.
A better system would be to be able to plant/mine/improve whatever the player wants in his home. Let's imagine something like: I'm a Ranger and I have to craft my arrows, I can do it in the open world collecting materials or I can go to my "home instance" to collect resources and craft. Oh! a high level boss is weak to fire, ok my alchemist profession allows me to collect some fire minerals in my home instance to craft fire runes to imbue my arrows and generate fire arrows.
A "BETTER" IDEA:
Mini mobile game: I'm one of those people who get hooked on MMORPG video games. And when I leave the house I want to play at least a little bit.
Why not implement a "home instance" for mobile where we can manage our resources, mining nodes, etc.? Or plan quests for our personal clan from the "home instance" as WoW did in Warlords of Draenor?
I have never seen that a "home instance" is shared between the PC game and the mobile game and is useful to progress in the game.
Yes we plan on making a companion app, where you can log in the game and play but with restrictions, the idea is to manage your main things, not to go to raids and dungeons from your phone :D