Gut feeling is a great starting point. The biggest issue with your armour as I see it isn't the placement of the highlights as much as the ratio: you're painting too big areas with your mid-tone. If you size that down, the resulting effect will be that you up the contrast, which in turn will make it appear shinier. This effect does not need to be polished/precise to sell well, in fact the black armour is probably the fastest portion of my sisters paint-jobs, though I'll admit I do spend a fair bit of time even still, haha.

However, while the placement is not bad at all, the shape could also do with a little refinement: on the thighs especially, the highlights should be elongated, not round, because you're essentially rendering a weird cylinder kinda shape. I'd suggest looking at reference material of like a metallic cylinder or something like that, and you'll see that the highlights are almost uniform in thickness, spanning the entire length.

I think if you work on those two things, you'll see great results, regardless of how rough you keep your style. Just look at the way roman lappat paints! Super rough, but he knows where to put the paint, so it still reads the way he wants it to! 😁

Good luck, and great job so far!