Hilda Scotland could only exercise the right to control is own land, territorial waters, and finances if it was fully independent of the UK. And it is oil not gas that is the major asset. The Westminster government have been predicting that oil was about to run out for 40 years {Please google the McRone Report} but it continues to flow and new fields are being discovered. Hopefully, within 30 years we will all have gone over to renewables and it just so happens that Scotland - blessed with an extensive coastline and many firths (=fiords) and a temperate climate (= usually neither too hot nor too cold, neither too windy nor windless) and umpteen lochs and fast flowing rivers - is ideally placed to benefit from wind, wave and water power, not to mention reserves of shale and coal, which could be utilised if needed now that carbon capture technology is well developed. Currently, Scotland is a net exporter of energy (to NI & England, via the grid), when all the tidal and wind projects come on stream, Scotland will be entirely self sufficient in energy for the forseeable future.
Jess Obviously you cannot have 9% of a single naval base but I think you will find that with all the recent closures and cut backs Less than 10% of bases are within Scottish Borders now, so a proportional division of bases copuld be achieved simply by each keeping what we have already. It is proposed that Scotland will have no nuclear weapons on land or within her territorial waters* and that Faslane will become Scotland's main conventional naval base. There are suitable deep water ports elsewhere in the UK but politicians are worried that no one wants them near to where they live (neither do we!). As the nuclear subs are ultimately, under the orders of the USA why not let their government find a base for them?
And Yes, the National debt is taken into account in the figures. Scotland will not of course have to pay off her share in one go but would continue to make payments of mainly interest as at present. Scottish people are of course paying their share of the national debt through their taxes now, when these taxes are payable to the Scottish Exchequer there will be exactly the same amount available for paybacks.
*No Nukes in territorial waters would apply to USA, French, Russian, etc. vessels as well as those of Rump UK.