I wanted to add some input into the proposal, mostly concerning your player housing idea. I would first advise looking at how other games handle player housing. The main games that player housing enthusiasts enjoy are Everquest 2 and Rift, so I would suggest examining how they implemented theirs. I would also like to emphasize that you should make true player housing, where you can place, resize and move items. Another essential thing is the ability to add permissions for certain players, allowing them the ability to move and add items in your house.
Secondly, I think that gaining items through the open world is an excellent idea but it is also a golden opportunity to add housing items to existing trade-skills, for example, armorsmiths could create decorative suits of armor, tailors could create cushions, beds, etc. These items could then be a way for these trade-skills to make a profit. In addition to this, consider allowing people to add crafting stations to their houses, which would add utility.
I would also suggest that housing items should be tied into other parts of the game. For example, adding achievements to kill certain world bosses could give a trophy, as well as completing slayer achievements. Zone completion should also unlock vendors with unique items from the zone.
Another area which would benefit from this is the living world and personal story – whether through drops, meta and achievement rewards or through a Zenith Weapon style locker. This would enrich the feeling of actually gaining meaningful items. When you implement the ‘grail quest’ idea, housing items could be rewards, ’cause it would be awesome to have trophies and mementos.
Finally, I think an important thing is to realise that some people like building from scratch, while others will just want to decorate. Add housing in cities first, then add housing in the open world. I would also like to suggest tying housing into the gem store in some way. Just don’t make all the cool stuff gems only.
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