Triangles/Ngons can be bad if you're using them in detail areas to define shape. If you've got a triangle in a flat area of your mesh that isnt defining a curve or anything, its perfectly fine. I use ngons quite a bit to transition from shapes into different shapes, often you need different types of tesselation/geometry to…
I'm not sure if this is the issue you're talking about, as I'm finding it a little hard to see precisely what you're talking about in your image, but one problem I see with your mesh at the moment is that you've not got any edges defining the outer curvature in your inset segments. That means that they're staying very…