5 UV sets?
This will cost at least 5 draw calls. Draw calls are a scarce and precious resource.
They are much more costly than extra triangles.
Use too many and your frame rate drops.
When you build and decorate a proper level, the draw call count goes way up fast.
This is the first thing I am always fighting with when optimizing a level
draw call count not the polycount
I wouldn’t want to have 5 draw calls without a very specific reason and an extremely important level piece.
even then I question the wisdom of doing it that way.
I think your model is identical on both sides, If not. It can easily be made that way.
I usually accomplish this by building half a model, unwrap it and then when it is unwrapped make it symmetrical.
This trick will double your texture resolution
Jam the other 3 UV sets into all that extra space you just got
I try to keep only the lightmap on its own channel.
The only time I use extra draw calls is if the shader is just completely different for one texture.
Like glass or water vs a hard surface