I was wondering if there are any LOD mods or other mods that improve the quality of middle distance textures as well as distant lands. I already use Qarl 3 redim. As far as I know the LOD improvers are designed for distant land textures. Can someone suggest something which may help? I have a middle range PC by modern standards. Thanks.

The way the engine works there is no "middle distance" really. The only thing that comes to mind are mipmaps, which are basically smaller versions of each texture included in the texture file, but unless the ones for the textures you already have are exceptionally bad or something, there's really nothing that can be done to improve upon what's already there.

It might be helpful if you included a screenshot illustrating the issues you have with "middle distance" textures.

EDIT: Another suggestion would be to increase Anisotropic Filtering as high as you can in your video card's control panel. It will definitely increase the quality of textures at a distance from you, without it they get blurry, basically. You may have already done this though, it's a must for me.

The "middle" distance you speak of is just a fade effect shader between the high-res near textures and the low-res DistantLOD textures. You could try Koldorn's LOD Noise Replacer to make the effect a bit subtler, but there is no way to fix the "middle" distance. Especially, as pointed out above, a middle distance that doesn't even exist.