How far to go with this eh, some ideas:
To avoid rope drag make sure you have longer extenders (how many people do you see climbing with a set of quickdraws only).
Sort out rope signals for situations where communication can become difficult such as bigger walls and sea cliffs.
You mentioned a rain jacket, but also water and sun screen are important to avoid heat stroke – even on winter days this can be a problem when you are out in the sun all day.
Use tensioned belays to avoid shock loading if and when a fall occurs, also best to not be part of the system and have the belay device tensions directly to the anchors (i.e. an escapable belay system).
Stating the obvious make sure people know where you are and when you aim to get back.
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