And yet, that's EXACTLY what Personal Housing is. Personal Housing: "owning all of that space only for yourself, and probably do nothing with any of it but make it look pretty for no one but you to see, meaning that is 1 less house for actual group FC's out there to have."
I'm not sure why you are targeting the minority here (solo FC's) when it's Personal Housing that is wasting so many plots. Solo FC's put that same plot to far more use by default. Furthermore, when housing was released it was ONLY available to FC's (for 9 entire months.) If people wanted to own a house of their own (instead of an Inn room) they were forced to make a solo FC.
On topic: There is no limit to how many workshop materials you can hand in each day (despite what the workshop NPC says.) Collect ALL of the mats you need for every phase for multiple items. -Then- invite three people in Duty Finder; pay them for their time, and be on your way. I completed 15 Progress phases (5 different projects) in one fell swoop. It's easy - there are so many people that are Idle in Idylshire who would be happy to make 25-50k for AFK'ing in your house.![]()