If this is a modular piece, why don't you go all in. Use trimsheets and tilable textures on top of the vertex blending. You don't need a highpoly to lowpoly workflow with unique UVs/ Textures for this
A trimsheet can be as complex as you want it to be. You could use a tiling default concrete texture on UV set 1 und have wear or other things for Edges on UV set 2. Or use decals to do that.