It looks really great, so clean and simple. I have shared your photos with my husband and those along with the easy to keep clean appears to have swung it in favour of boarding. (interesting as I'm the one who cleans the bathroom :) ) I will get some samples and then we can finally make progress thanks to everyone for your help.

Thank you plusmarcus. So my thought about the side panels was how do you decide where the bedsides go? Do they sit in the middle of the side panels or do they sit so that the two beads line up with the middle of the bedsides? If you put the bedside in the middle of the side panel they are too far from the bed. And if you put them so the beads are in the middle of bedside they are too close? With the original "B" photo I wondered how the proportions would work with bedsides. Would bigger bedsides in the same style as the bed work better? Sorry might just be my OCD, but where you have them now, for me, throws off the original proportions.

Ooh that’s a big hall to add panelling to, but if you have the budget and the manpower it will look pretty amazing.

By inlets, do you mean the recesses? I've just had Multipanel panels installed in my new bathroom. External corner trim was used around the window, but a piece of solid surface worktop used for the windowsill.