I'd break down things honestly. Making several smaller textures 256x256 or using one 512x512 etc etc Having 3 different tiling metal wit bolt placement 3 different bricks in a row that tiles. Just smart layout of textures, what you're doing now just makes it harder for you to make changes. Especially if you have curved…
I am abit unsure with the chimney texture, I am trying to achieve a scrapy look as if multiple sheets of metal have been bolted on. More work needs to be done for example more bits of dirt and scratches, also mabye some variation in colour on the metal. Many thanks for your help