The exeception is the fuel silo - I never ever bothered with those. You get a decent fuel reserve by industry alone. And just to be able to store more will not help you in the long run without enough fuel production capabilities.
Do I oversee something here? Is there a nation or a specific playstyle in which fuel silos are useful or even essential?
What you call a Decent Reserve is in fact some 100k fuel for medium minors.
Imagine what happens to in once items in
research slots #4 and #5 will get set-up and running? At the beginning of
1943 my SHBBs are also coming from the refittings with top engines aboard, and those too act like fuel 'refineries' of their own.
It's not like I can import fuel either. I.e. over here I've recently finished off my SHBB construction program by importing metals at the expense of 2'000 convoys I stockpiled in the early days (when it's inefficient to produce ships anyway due to lacking modern designs). Either way, this option is now apparently gone (capturing Norway could grant some 200-300 convoys, those would last for 4 months tops).
When you sit there all alone, and mighty Amerika is on the other side of the globe, your only option is to run a series of pulsed offensives (which includes fighters on Air Sup), and you do this by having some amount of fuel *stockpiled*, since no realistic amount of Synth Refineries alone could sustain a modern fully mechanized, jet'ized and STR bomber-equipped army, which is planned to get ready
once the last ramnants of wannabe-exiles join the club (allowing their host to finally go fascist and save the world).
[Should have got Synth Oil Experiments far earlier, but I blame spies who kept going back with stuff like Basic Fire Control - when I already had Advanced one researched and put into service]
P.S. The game is so much more interesting when Britain, Germany and the Soviets co-operate against third parties rather than exhaust each other in a triangle of wastage. Hopefully, this sentence addresses your inquiry for 'specific playstyles' in its utmost clearness.