Professional Voice Cloning - Sentences length?

Besides those tips from Elevenlabs, that are mainly hardware :

Is there any impact from the length of the sentences we read? Like if only read short random sentences, is it ok?

For the style, should you keep a consistent style like maybe monotonous voice or should you have the full range?

Also, did someone try a 30 min and 3 hours of speech to see the difference?

If anyone that managed to get a good voice cloning (meaning close to reality) wants to share what kind of script they used it would be cool.

Thanks