My new game environment in unreal engine


My college course is Games & Animation Designer Diploma Level 3

I’ve taken this screenshot from the first region and is called Pacifica in the unreal engine. I will create futuristic game called as Pacifica’s Last Fate is inspired by Avatar the Last Airbender and Genshin Impact.
I decide to created 8 regions but i have to focus on 1 region because I prefer patch roadmap.
My props in default landscape- Brown-spotted sheep, wood crate, daisy flower and melon slime.
What ideas will you like to add in my new game?
do I need music and voiceovers in this game?
Should I use Blender or Maya model?
Can you tell me what I need to improve my game ?
Please reply and leave your comments for me if you read this.