2 MOST IMPORTANT THINGS TO KNOW ABOUT SCALE:
Base scale listed in this article is a good starting point. These dimensions will work 9 times out of 10.
Few things to note:
Scale and dimensions of your character and architecture is going to be relative to your game and the environment you are creating. Character collision boundaries will play a significant role for various architecture elements such as doorways height and width.
Scale and dimensions have to “feel right”. It all depends on how the player perceives your environment. So if you created “most-realistic” environment that match dimensions from the real-world but when you walk around it feels small, then you need to re-work your environment to make sure that your level “feels right”.
Remember: Everything is relative to the player and how the player sees the world.
Use these base values as a starting point but you may need to modify them to fit your project.
You can find the full article here. Plus there’s a bunch of images and a video. If it’s not enough, check out official UE forums.
