Yeah it sounds like React's Components could be similar to Unity3D's GameObjects and the replacement for mixins could be similar to Unity3D's Components.
E.g. implementation: SubComponent (or something named better), a component can add the subcomponents to itself on initialization, and the lifecycle events can be similar to the Unity3D's SendMessage, i.e. similar to mixins. I think it would work quite well!
You would need to get the child subcomponent specifically e.g. get the timer subcomponent to create a timer, but as a bonus the subcomponent would not edit the instance of the component, feels cleaner TBH. Also two subcomponents can have the same this.field or this.property, or this.func without worrying about whether it belongs to the Component, another mixin, or something else :D
E.g. implementation: SubComponent (or something named better), a component can add the subcomponents to itself on initialization, and the lifecycle events can be similar to the Unity3D's SendMessage, i.e. similar to mixins. I think it would work quite well!
You would need to get the child subcomponent specifically e.g. get the timer subcomponent to create a timer, but as a bonus the subcomponent would not edit the instance of the component, feels cleaner TBH. Also two subcomponents can have the same this.field or this.property, or this.func without worrying about whether it belongs to the Component, another mixin, or something else :D