Hmm. My instincts suggest that full councils early on is a needless dilution of BP, but thinking about it the card-generating councils ARE more efficient per BP than the strategic council you start with, and one could potentially aggressively budget to divert funds towards the more critical councils early on. It might also be of some benefit for a beginner to start with all councils unlocked just so that they know what the councils actually DO so that they can make more informed decisions later.
However, I really don't know that starting with a council or not ultimately makes that much difference to difficulty, and it's hard to call it essential for a beginner.
As far as the other tips go...
8 is based on a misunderstanding. You don't need roads to hex perk assets to benefit from them so it's absolutely worth it to send troops out into the wild to pick up a refugee camp or something. That being said, following roads usually leads to minor regime cities and you want to be eating those as quick as you can, so it's not like following roads is a bad idea.
9 means you're building too much for your economy. The issue isn't that building is necessarily slower than predicted, the issue is that you don't have enough resources on hand to supply the construction's per turn needs. The solution is the same in either event - build at a more measured pace - but it's worth noting that once your economy is stronger it's entirely possible to build on time and on budget even with multiple construction.
10 isn't necessarily true. In fact, you can bugger your economy if you nationalize the starting private asset farm because the private economy needs that to not starve, and if the private economy has no farms the only thing they'll do is try to build a farm to feed themselves. Logistics buildings should usually be nationalized, and resource production buildings are worth nationalizing if you need those resources (the starting scavenger asset for instance is quite valuable), but otherwise there's benefit to letting the free market run - if nothing else, nationalizing everything means you go broke because the private economy is starved of taxable income while you're paying more and more in salaries to public workers. Broadly speaking, public assets are how you gain resources, and private assets are how you help gain credits.
12 is partially true. Major diplomacy isn't worth focusing on early, it's true (and arguably minor diplomacy isn't all that important early on since you mostly just want to find factions to eat in the early stages), but spying is pretty critical because it's the fastest way to identify rich targets for expansion. Further, if you have a full council I don't know that focusing on the supreme council is that great a strategy since they're less efficient in card production in every category than the other councils - they're important for their PP production, but if you have a full council they really don't have much business producing cards. Early on the standard advice is to focus down on the economic, military, and model design councils.
14 is...kinda true? Good leaders are necessary via cards, preferably profile-specific cards, it's true, but while it's not a great idea to spam junior leaders I have a hard time seeing how you'd spam so many they'd become an active drag on your economy - like what the heck are you DOING that reserve leaders suck up that much of your income? It's almost always worker salaries that form the real drain on your economy. For that matter, why would you need so many leaders early on if you already have a full council?
21 is...a bit iffy. Factories are nice but they're non-critical in the early game and more importantly they're incredibly expensive metal-wise. Until your economy is in better shape it might be best to hold off. Metals are absolutely critical early on though. And farms are pretty key as others stated since you're probably not starting the game with a food surplus and it's only gonna get worse as your army expands.