The light come out can be switched off if you don't like it. In my opinion they generate stunning pictures. There is also a pro mode. Here you can change lots of parameters.

i was very disappointed with the pictures at first - not authentic at all. disabling AI was the best improvement for me, and using authentic mode only. i use pro mode if i want a really good picture.
portrait mode does not a good job at clearly defining the outline and bluring only backround, edges of subject are blurred as well.
overall i bought the phone because of the camera and would not buy it again. samsung / iphone / google pixel are better options

You can deselect the Leica mode and use another one, but I think the Leica is good

Hello, you can set it manually between two colour modes. Leica Authentic and Leica Vibrant. I hope this helps you. Unfortunately I can't say any more about this