Sine.Spaces uses Deferred rendering. So you can use as many lights as you wish.
Below is the Unity5 documentation for scene lighting. It's a bit long but worth the read.
Here is a video on the basics of light.
Baking your lighting will help with overall performance.
1. Make sure any objects that are not moving are set to static, you will find the tickbox upper right
corner of the inspector when you select an object.
2. If the object moves in any way leave it unchecked.
3. Go to Window > Lighting
Be sure the following are checked:
Precomputed Realtime GI
Baked GI Setting
Select the Baked option under Ambient GI drop-down box.