Learn English – “If” and “would be” when talking about future events

For centuries the standard way of re-telling the events in a narrative or drama has been to express them using the ‘present’ verb constructions—simple present, present progressive or present perfect.

The notion, I suppose, is that you depict the events not as something which happened in the past but as a story unfolding in your presence, as if you were hearing them read or seeing them performed.

In these narratives the specific time referred to is constantly moving forward - just as it does in ordinary past-form narratives. Consequently, when at any given point in the narrative a previous event is alluded to, that event may quite properly be named with a past tense.

That is exactly what your two actual examples do. It's not clear what your hypotheticals are hypothesizing, but the first appears to project what Chapter 6 will write. It refers to a current event, growing her hair back, in the present, but employs a past form to describe the head shaving, which occurred before what is the "current" present.

I cannot tell what the others are supposed to represent. They appear to be comments on the content of the narratives rather than the narratives themselves.

So, if I said it grammatically correctly "I like my new car", would people think that that sentence expressed a permanent or temporary state?

For stative verbs such as like, the simple present is a neutral form, not implying anything about permanence or temporariness.

If you want to emphasize that your feeling is likely to be temporary, you can preface your statement with "right now".

If you want to emphasize that your feeling is likely to be permanent, I think your best bet is to add something that ties your feeling to something about it: "I like my new car much better than my old one", or "I like my new car; its all-wheel drive is exactly what I need on snowy days", or . . . you get the idea.