I appreciate the input, certainly. However, I'm very much still in the beginner phase. I've "worked out" for a while, but not very productively. When I got over myself and started this program over the summer, all but the bench were new exercises to me and I started with the bar. I shouldn't be at plateau stage for any of these exercises (my squat made it up to 145 lb 5rm [also my body weight], OHP only to 85, everything else was somewhere in between those numbers).
My real issue I believe is simply technique and mobility. Back position, stance, that sort of thing. [Real talk, none of these movements were natural to me. Air squats didn't even feel good. "Hinging at the hips," "loading the hamstrings," even "keeping a neutral spine" were not only foreign phrases but they weren't and still aren't natural for me to do.] Real early in the program, my hips were killing me. I narrowed my stance on squat, fixed that problem. Then with a little more advancement, my glutes were killing me, and I noticed I wasn't achieving depth (not getting down to parallel, just above). So I took a little weight off and went as deep as I could. Well, then the back problems started up. First the issue in the lat area, then the lower back. After a period of recovery, I noticed that going down deep on squats (well below parallel) was resulting in posterior pelvic tilt, which can lead to back issues. So I'm now working on achieving parallel, maybe going a bit below, but not all the way to the ground, and am trying to keep my back properly aligned while doing so. Along the way, I experimented with low bar versus high bar, but I think I'm just going to stick to high bar for now.
So, as I said, just working through a lot of technique things. At the same time, my OHP and bench weren't progressing too well, I was losing endurance, and I suspect that maybe even some of the other issues could be due to uneven gains. I'm hoping, not just on my own thoughts but based on information gathered, that a lean towards doing more volume will help me push through.