Some look rather more Scottish than others, but here goes:
Frank - prefer
FrancisJack - good as a nn
Jonathan - dislike: long and dull
Randall - shortens unpleasantly to
RandyFraser - family name; like very much
Jamie - like only as a nn for
JamesReginald - unattractive
Lamb - eh?
Graham - like very much; pity it's dated
Colum - unattractively architectural
James - like very much, enough to use
Arnold - dated and drab
Hamish - quite good fun; prefer
James (there were brothers, twins I think, who played cricket for New Zealand and were named
Hamish and
James, which I think was a bad idea)
Murtagh - dull and clumsy
Alec - like very much; favourite nn for
Alexander and also good as a name in its own right
Dougal - quite cute; prefer
DouglasRupert - the Bear?
Robert and
Robin are both family names, and I'd use
Robin so there's no room for
RupertMacKenzie - only if it's a family name