Sentences

One idea at a time.

Length and load

Difficulty comes from packing several ideas into one sentence, not from word length. Splitting an overloaded sentence is the single most effective edit available.

Vary length; a short sentence after long ones lands hard.
Keep subject and verb close together.

Order

Put familiar information at the start of a sentence and new information at the end. That flow is what makes paragraphs feel connected rather than listed.