Some more thought on negations:

Actually, I do not think that the negative sentences are a very special case of aspect usage. It seems the basic rules are the same, but there can be some nuances. Although I might be wrong...

Just some more examples:

Someone has got a trauma. A doctor reassures his spouse:
Не волнуйтесь, травма не опасная. Он не умрёт. - Do not worry, the trauma is not dangerous, he will not die.

Perfective is the only option here. Although "он не будет умирать" is grammatically possible, it is hardly ever used as it creates an impression that "he can die multiple times".

An opposite example. One decided to stop drinking alcohol, and he promises:
Я (больше) (никогда) не буду пить. - The words in brackets are optional: "I will not (ever) drink (anymore)".

The imperfective is the most suitable for this situation. However, "Я больше никогда не выпью" is also possible, but it creates the special effect when a speaker substitues "specific for general": he is talking about the future in general, but he refers to it as to a single specific event. And I'd say it does not sound as his firm decision not to drink ever, but rather as his regretting he will never have a drink anymore due to some external reason. It seems to be a more complicated stuff for advanced learners.

Moreover, the imperfective in this example is possible with or without additional words (as I mentioned above):
Я не буду пить. Я больше не буду пить. Я никогда не буду пить. Я больше никогда не буду пить. - All sound fine.
The perfective is only possible with "больше никогда". Just saying "Я не выпью" does not sound right in this context. It can be possible when talking about a specific event, but not about the future in general.

One more observation: future perfective negation is also used to express one's physical inability to perform an action:
Я столько не выпью! - I cannot drink so much!
Я не подниму такую тяжёлую вещь. - I am not able to lift such a heavy thing.
Я никогда не выучу арабский язык. - I feel I am not ever able to master Arabic.

On the contrary, using imperfective in those examples means one's unwillingness to do something:
Я не буду столько пить! - I will not dirnk so much (and do not want).
Я не буду поднимать такую тяжёлую вещь. - I will not lift such a heavy thing (since I do not want, not because I am unable to).
Я никогда не буду учить арабский язык. - I will never learn Arabic (I do not like the idea).