It is all niche related.
I have a niche, where 90% branded is perfectly normal, since some of the big players have been around for decades(were paper magazines before the internet), so people know them and cite like that. Do that in a different niche and you'll look ridiculous.
In most any other niche I am in, I ignore all "rules", like 40% this, 32.5% that... I just use what feels best. Like if it is in a post, would it be better to is the naked link, branded, or some linked word(may not even be the keyword I want: post is focusing on fertilized dirt, I may link soil). Just keep it as natural as possible, in the end, the goal is to get the google bot to your site, then let Google work their google-fu to figure out what my post is about.