Hi Tony
Thank you for your thoughts.. ..
you may not know that I am a complete novice, only venturing into electronics as a hobby after retiring from teaching last November and as such I was impressed, if not surprised that this creation of mine actually works, and consequently, the finer points you mention are icing a cake I don't yet have. Having said that, I'm always grateful for the comments because it gives me something to explore on those dark winter nights and learn from for the future.
I did consider adding paired outputs but as all the grounds go back to a huge block of solder on the PCB only inches from the front fascia, and with my current ability I'm not likely to use more than two outputs at the same time, I decided it was unnecessary. For the same reason, I can't see heavy loading of any output being a problem.
This was as much a project about practise as practice, when I've got another 12 months of the benefits of being a member of this marvellous forum, I'll build another PSU that opens the front door when the bell rings and tells jokes to visitors !
I appreciate your help, as usual
S