Your trouser looks like it might be of the correct material (still bleached though), the other ones do not.
They are very white. Proper unbleached linen is almost brown, depending on the type of linen and whether it has been washed before or not.
Look at these samples I have at home. 2,3,10,11 are partly bleached. That is why they are so white. Anything from 5-15 is strong enough to be used as trousers, gaiters or for other uses. Anything above that is to thin and will rip apart to quickly, or let to much air or dirt through. 9 and 15 are the same, except 15 has been washed in 90degree warm water.
The actual colour of the linen heavily depends on where you got it from, so the colour varies, but it is never very white. As a matter of fact, the wool on your gilet/habit should be whiter than your trousers. As you see, the whitest unbleached linen is still very brown.
The pattern that bardin trousers should have is the pattern you see on number 12. Ofc. there are still regimental differences, and I do not know about every regiment specifically, but in general this is how it is supposed to be.
About the cooking stuff:
For civil war, it is actually reasonable to use a dutch oven. Unless on campaign ofc, carrying it would be an absolute pain. What really bugs me everytime about the civil war, is that no one seems to carry any large cooking gear. I guess I got so used to carrying the pots and pans around in Napoleonic and WW1 reenacting, that I wish I could do the same in CW, while still being authentic. I hate to just have a cup and a canteen half to cook with.
Anyway, here are the pots I was talking about:
My idea with the canvas bucket is just an idea. As far as I know, it was never issued. However, the thing on the back of the soldier looks exactly like a water bucket would look like when folded up...
It could ofc, also just be a pot in its linen cover.
The one below one we know was not used a lot. Soldiers threw it away, or it rusted away to quickly. Its sole purpose was to carry water.
It also was not issued after the Napoleonic wars, so we have more or less definite proof that it was not used.
