For me, “Histogram” will always be on. It gives me a quick glance on the overall exposure of the scene, whether or not I have clipped the highlight or shadow too much and adjust my settings accordingly. When shooting landscape, histogram will be useful to employ the “expose to the right” method to ensure as much usable data is being captured for post processing later. Talking about shooting landscape, you may want to activate the “Electronic Level” too to ensure your horizon is levelled.
For those who just started shooting, feel free to activate the “Framing Guideline” (such as the rule of third frame line) to assist you in learning how to compose an image using the basic composition rule. Once you get familiar with composition, feel free to turn it off if you find the frame lines distracting.
If you want to do zone focusing or manual focusing with your lens, activate the “MF Distance Indicator” and it will show you that at current Aperture and focusing distance, how large will be the depth of field (or in other words, how much of your picture/subject will be in focus). If you wan to see the same thing when you are using AF, just activate the “AF Distance Indicator”.
These are a few items which I find useful. Feel free to explore and customize your own camera to your shooting style.