I thought this up kind of out a whim. Out of the blue thing.

Here it is..still very rough though.

You start out as a trainee. You basicly help out doing basic things: Feeding, Bathing, Cleaning..so on. While you are doing those, you will also be tring to achieve goals. So..Say it says...feed 10 animals hay, bath 5 cats, 10 bears, and 15 elephants. Then there would be clean every cage 30 times.
After you do those, you go to the next level, what ever that is..maybe Loner. This is where you are alone. You will still have goals. Harder as you go and also longer.
Then Coach, where you help new members, new goals, again harder, and takes longer. After that you get to manager, VP and Owner.
During these you will need to find items to help you. If you need to feed an animal, you have to find the shovel, pitch fork or what ever you need before hand. Then you would need to gather the food, prepare the food and feed them. If you give them to much, they get sick, which means a Vet would need to be called. If you dont feed the enough, they starve and you fail, then have to buy more.
Once you get to VP, you will be in charge of the zoo. Bills, pay..so on. You will also be responsible for finding bugs, and things, like the other LDW games. This is ONLY once you get to VP.
As a owner you would be able to decorate the zoo. To make money you would be getting donations, and suport via the hood. This will be done by fairs, get to gethers, events. Also get money from members visiting. While this is going on, you will be tring to get 10 stars. This is done by making sure the animals are good and healthy, staff is happy, and more.
I hope this is a good start..
Ive been thanking about this all day lol

The Vp part..you could collect insects, birds, or other things to add to the zoo. These then could be added once your the owner and added the insect house or bug world.