1. No
2.No need, black and white LCD is more comfortable in day light and consume less power.
3.Both is ok, But cable inside the shaft is last longer.
4.6 inches, 12 inches, 18 inches(for people who hunt for really deep relic 1.5-2 meters)
5.Great.
My suggestion
1.Compact and lightweight
2.Use 26650 battery