My future virtual gardening software

Warning: this is a thinking out loud post, so it probably won't make much sense

I'm thinking about writing a virtual gardening program, mostly to keep up on my programming skills. (I've been neglecting them woefully.) I'm still trying to figure out what I want.

• I want to be able to plant plants, see them grow over time, maybe see the seasons change.
• I want to see birds, bees, and butterflies arrive.
  
• I want to be able to water my plants, but I don't want to HAVE to water the plants.
  
• I think a 3-d program would be cool, but I don't want to have to support all the modeling, maybe I'll stick with 2-d, kind of cartoony appearance. What would be cool is if I could export to a format that one of the on-line 3D gardens programs use (like http://www.bbc.co.uk/gardening/design/virtualgarden_index.shtml), then I could walk around it if I wanted to.
• Grow vegies, maybe be able to pick the fruit and the flowers.
  
• I'd like the option to let the plants seed down, maybe with lame models of how they do that.
• I'd also like the option to speed up or slow down time. Basically from "one day is one day" to "one day = one second". Maybe a pause on this day.
• I'd like to be able to save the garden and load the garden.
• Also maybe take screen shots
• put in rocks, fountains, maybe a bench (the disadvantage is I have to draw all these things, ack!)
• It'd be cool if the plants would sway in the breeze, but I don't know if I'm that dedicated to the graphics.
  
• maybe some nice peaceful nature sounds (birds, crickets, bees, wind).
• I actually really like that I can grow plants in Dogz 4. That's my favorite part of the program. I'll probably end up doing something like that.

I think actually doing all that would take forever. I think I'll start with putting a few plants on the screen and watching them "grow".