I'm confused at how から works, and there's very little information on this subject.
だから is used in front of a な adjective or noun.
い adjectives simply use 「から」.
Verbs can be in ます form, and only use 「から」.
Can 「ですから」 be used in place of 「だから」? And is the difference between:
「早く寝ましたから早く起きます。」 and 「早く寝たから早く起きます。」 different to each other the same way any typical plain form - ます form pair of sentences is?
Does the same apply to 「猫が綺麗だから犬が怖くないです。」 and 「猫が綺麗ですから犬が怖くないです」?
Can 「ですから」 be used in place of 「だから」?
Technically, yes. In practice, no. It's very rare to use ですます調（敬体）in this situation. When a sentence contains the type of から (English "because") that you are using here, it always comes with a second part. As long as the second part is in 敬体 the whole sentence is assumed to be. So your example:
「早く寝ましたから早く起きます。」 and 「早く寝たから早く起きます。」 different to each other the same way any typical plain form - ます form pair of sentences is?
「早く寝たから早く起きます。」 is already considered "polite". That said, から here still feels more informal than ので, so probably better is to use ので in business situations.
The situation you may hear ですから is when the second part is not present, either because it is implied or because you are answering a question.
Does the same apply to 「猫が綺麗だから犬が怖くないです。」 and 「猫が綺麗ですから犬が怖くないです」?
Sorry, I don't actually understand what you are trying to say in this example.
