Hi Denis,
I bought replacement tanganyika strips for the job. I have the same thing, width is very variable, up to a 1mm variation (0.5mm under or over) which really surprised me considering it came from a specialist ship building site and is the product of a well known company. At 0.5mm thickness I'm finding it is brittle also. I think I will try to build a block of cut planks and sand the edges. It also seems to want to curl when glued. Have to be honest the 0.5mm laser cut walnut in the ZHL kit is much better! But too dark and a little wide for what I wanted.
To me your work looks excellent. It is always the same with us modelers, we never see in own work what others can. We only see we could do better. It will always lead us to another build though. ;-) The images are very helpful, as I can see how you approached doing it. I would be more than happy if I could get my deck planking even close to your overall result.