An independent Scotland would come unstuck for all the reasons previously stated.
Rump UK would suffer worse without the Scottish votes to deprive the Tories of a permanent majority. The current regime's return to Thatcher's Victorian Values such as mass poverty, falling real wages, underemployment, children with rickets, epidemic depression, growing slums and overcrowding, sick and disabled people left to rot... ... is an indication of the disaster that awaits us.
The first article:
Blackwood's Edinburgh Magazine, March 1851. illustrates the horrors that would follow.
On the topic of London, I have worked there, have friends who live there and my two longest standing friends were born there. It is a great city to live in - for the well off and for the culturally inclined. It does get a disproportionately large share of state spending on transport and culture. Far more so than Scotland ever has. Its influence tends to work against the national interest since it is the UK (and sometimes planetary) centre of financial crises. The consequences of which are born far and wide outside its bounds. The UK is far too centralised.
Among my other friends, one was born in Radcliffe and most live in and were educated in Manchester and Greater Manchester. The quality of life for the less well off is much better hereabouts.