Or if possible add some feature to stick to some user defined dimension.

Even it is always said that all the textures should be square, power of 2 etc. in some cases a texture needs to be rectangular (and still be power of 2) instead of square.

When mixing these textures with square ones, in the library they would not look fine. So an additional icon is needed to be made on purpose.

Since we have the nice functionality of reducing the size of the textures to be used as thumbnails in the library, would it be possible to constraint their dimensions too? That would lead to deformation of course, but I was wondering if they can be "cut" to square when we create the thumbnail.

Again, automated processes to save time in the production side :)