A really good thread with many useful answers !
one poInt is like already mentioned that russia spents a bigger percentage of its military budget to actual weapon systems than nato countries do . In the western world much is used for salaries , pensions , social programs etc . The costs for keeping nato standarts of the infrastructure like air bases , naval bases etc is also not comparable to russian air or naval bases.
when it comes to actual weapon systems they 'fool' us a bit with sheer numbers but it does not say much about the combat capabilities . Old and rusty tanks or planes in storage look on the paper impressive but do not say much about true combat strenght.
Even never systems appear to shine only on the paper . Lets take the fancy s-400 air defense system . In theory superior to patriot , in practise in syria or armenia turkish drones and missiles were able to perform their mission nevertheless .
Russia never showed off military strenght big scale since ww2 , in fact they even struggled to force out few thousand rebels out of aleppo in syria , the same in chehen war .
I,m not saying its nothing what they have because it would be naive to assume it - but lets not overerstimate it .
When there was a comparision to the uk - I guess russia from a military point of view would just stall in a try for an all out invasion of the uk and trying to rise the russian flag on buckingham palace . ( assuming only russia vs uk )