My camera live in Aperture priority mode and auto ISO. Most of what I shoot is outdoors in changing conditions, and I care more about depth of field than anything else. So I set my aperture, and the camera worries about shutter speed and ISO. On my Canons I can control (to some extent) the maximum value it will move the ISO to, so I still have to watch the exposure rating in the viewfinder (on my DSLR) to make sure it's not reach a limit and is going to under expose, and I have to watch the shutter speed it's picking (which again, I can control to some extent) to make sure it's not going to blur motion unless I want it. But generally, the camera works it out properly and I get short notice shots that I want to get. I have to understand the exposure triangle (here's my blog on it, self promotion, https://perceptionistruth.com/2016/08/the-exposure-triangle/), but I'm not constrained by having to control all three elements at once. I use the time that gives me to think about the edges of the frame and the content which are more important to me personally than being out by a stop on the exposure. I use shutter priority and let the camera worry about aperture and ISO when I know I want to get motion blur (or avoid it). I shoot manual when I'm doing panoramas, so that I know I have consistent exposure across every frame. What I find more important than manual is understanding exposure compensation and metering modes. Getting to grips with those help you get the best from the semi-auto modes and reduce the need to worry about manual exposure. Understanding where manual exposure is the best choice is key and knowing how to achieve it is key, but it's such a low priority mode for a lot of people. Don't sweat it. Focus on the content.