To be broad you are looking at the game as a puzzle to be solved instead of as a real and therefore faulty and complicated issue. In other words you are in the game instead of above it.

To give some examples Colossus Smash is by far the worst of the three and shouldn't be recommended, Shield wall is really good against Valla and Glory to the Alliance is by far the best value/effort choice and most broad one, therefore the best choice for guide like this.

To explain something in between, although it would be most helpful, would take several paragraphs.

To be clear, I didn't read the guide, in fact I just skimmed through it but it said enough. I've actually just now read that you don't play SL and I do feel kinda bad, considering you did this for fun and with passion. It isn't good for the community to gatekeep content like this simply because it doesn't fit high standarts.

Now to the point. Why it doesn't make sense to have lower quality guide. New players need to learn about the game as a whole and about their prefered role, basic hero mastery is enough for them. Advanced players need high quality guide to compete properly. In other words, it's too thorough and complicated for new players and too faulty for advanced ones.

As to how to improve it, there really isn't an easy way. The obvious 'factual' mistakes can't really be helped, that's how you see it. The important thing is that the whole guide seems more like a report. All the numbers, descriptions and evaluations are nice if you want something to read or study but don't matter for people that want to use it. Just pretend you are a player that wants to up his Varian game and read your guide, maybe that will clear it.

I used ctrl+F to search keywords like 'boss', 'camps' and 'mana' and there are few brief mentions. Is it ok to try solo boss before finishing lvl 1 quest? Is it better to take camp or push empty lane? Do I have enough mana to E minions? Stuff like that is what the player needs, a set of guidelines and breakpoints that doesn't overwhelm them. What you've created is an information (significantly incorrect) that the players can build upon.