Cosmic Craggs

First thing to do is sell ALL those weird looking flower things. They are worth a ton. Pay off any loan. Reset your research to better accomodate what you are trying to achieve in that challenge. You can just turn off paths, other rides and attractions, water rides, and all that stuff you won't need to be researching.

Next, build a compact little park and pack in thrill/gentle/kiddie rides right near the gate and set up janitors and mechanics. I don't think you'll need to do any landscaping or roller coaster building. Easiest one ever.