Just a suggestion, but whilst there are just over 5 million folks resident in Scotland (the vast majority, 88%, of them native Scots), I'm sure you're aware that there are far more than 3 times that number in the Scottish diaspora living overseas, who now (through either heritage, birth, being ex-pat, moved with job or other reasons) claim some other land as their national identity - so it may make sense to offer them (and any potential new members) a choice when it comes to choosing which flag they feel best represents them or with which they associate.
So if you look at the main countries of the diaspora, and I know you already have some of these, you're looking at Canada, USA, Australia, New Zealand, South Africa, Rhodesia/Zimbabwe, Gibraltar & Bermuda, and I know I've certainly met them living and working in as far flung and diver places as Sri Lanka too. And that's before we consider the EU.
And one flag which needs to be added anyway, what ever you decide to do, is the Union Flag (Union Jack), as some people might claim, or prefer to be identified primarily as 'British' and not really identify strongly with any of the nations', principalities' or provinces' flags which make up the United Kingdom.
It makes sense - what do you think?
BoB
Is the Union Flag not there
Welshie! Why is the Union Flag not there? Tut tut!!!
MadWelshie
I am still working on it
BoB
Aye!
MadWelshie
It should work now
BoB
Forgot how to do it now, it was longer than a day and memory don't work as it used to.
MadWelshie
I thought you were able to multi task?
BoB
So I can, now what was I going to do?
MadWelshie
Them smilies, email.
BoB
Forgotten already, noo fit was it again
Oh aye, get rid of all that smillies that don't work or mean nothing
Do it later, no time
Can't remember the other thing I'll leave it to you to do it as you can remember
MadWelshie
I got rid of a whole load of the yesterday for you.
Tut tut!!!
Forgot how to do it now, it was longer than a day and memory don't work as it used to. 
