I'm in over 100 hours into this game - great game, can't wait to see more.
Easy way to add more 'value' to this game is customization. 1.) The upgraded house plot takes up so much realistate (while giving so little) this needs to be addressed.
But things like buildable fencing (ones you can craft yourself, not just buy), extra lighting for your farm, ect. People like to build and fancy up in these games - and it provides an extra time sink.