Just some little Ideas.
Add one or two really rare seeds (chance to get them about 1 to 1000) or take hemp and hops as this crops are more or less useless and add a curio which can be obtained from this crops like "hemp bud". U could also change poppys perhaps they should be easyer to get perhaps 1 to 100 as their curios are not so strong. So WWW´s would stay interesting not just in the first 10 days.
Limit High Q Nodes lets say u can just dig 50times the best quality, 55 times the next quality and so on, until they are at Q10 or perhaps empty.
Let new Nodes pop up.
I could imagine a lot people have fun looking for new nodes. (u could once per week/month let a good Node popup and add a server message where the node is, would be fun for factions).
Thats it, thanks for reading.
PS.
-Go Kickstarter or Greenlight
-Add a new World every 4-6 Months with the new updates but let the old one life.