How can I improve this UV-Mapping? I'm very noob in Blender as a result I'm struggling to unwrap a M24 grenade 3D-Mesh properly.

My first attempt to improve the UV-Mapping was making the irregular polygons as squares or rectangles using a Python plugin so that I could apply textures easily on Gimp. The result is this one:



Despite doing this I'm still not happy with the changes as the trial texture's squares are not well distributed. As you can see in the photos those parts divided by the seams have like a "cut" in the texture and I don't know if that will affect the texture added with Gimp.



Could you provide me with some tips to improve my UV-Mapping?

Thank you very much for your help.
Héctor
to change the size of these squares, you should scale uv-islands. this time it is y-scale. after you are happy with squares, you can scale island on x and y simultaneously to occupy most of available texture space. the biggest island should be the island that will show lot's of texture details. and you can also rotate the islands by 90 degrees.