Thank you for your comments, Rosko, Mike, Jørgen and Erik.
Erik - I'll try something along the lines you suggest; the print needs something and that might be it.
James - I was a late adopter of digital, because I loved film and I loved the darkroom. But when I understood what digital can do, and what doors it opens, I went over to it completely, without regret. But I still love film, and the remarkable thing is that even when it has been digitised (scanned), film retains all the qualities which make it different to digital capture. I find it hard to say exactly what these differences are, but it is to do with the purity of colour, with film's ability to hold saturated colour without looking wrong or "pumped", and with the biting sharpness small details - something here to do with the fact that exposure and development make physical changes in the emulsion; details are, in a sense, etched into the film. So when you have a piece of film, sharp, well-exposed, with a full range of tones and that wonderful colour that Fuji film was capable of, then have it professionally scanned, the resulting file is truly thing of beauty which can even survive conversion to monochrome.
I'll swap you a print of my Monument Valley for a print of your cactus - nothing to grandiose, maybe A3 or A3+ ? I'm currently printing on Ilford Prestige Smooth Heavweight Matt; a lovely, super-smooth matt art paper with a very white base (which I favour).
