I typically create several UV maps:
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A mirrored map for bump
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A non-mirrored map of the entire model to be used for diffuse, specular & roughness
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Sometimes I create specialized maps for alpha masking or special effects. For example, if the model has a couple sections where modeling holes would mean lots of extra geometry, I make UV maps of just those faces and then take all the other UV faces and shrink them into a point in the UV map. I then use that UV map to create a transparency mask for all the parts that need holes in them. Isolating the map to just the areas that need holes lets you have much higher resolution for the alpha map. It can also save a lot of polygons. For example, the deadlights on my USS Monitor were not modeled. They are created in the shader via an Alpha UV map. The water streaks across the deck were also made from a dedicated UV map. I created a planar projection of just the deck and used that to mask the flowing water.
If you’re not getting the resolution in your UV map that you want, don’t forget that you can use UDIMs to spread your texture across multiple UV spaces.