I've more or less finalized my new first unit in Physics 1. It blends the old first unit ("Preliminaries") with the first half of the old second unit ("Motion & Inertia").
It spans the beginning of the year to all the motion as we need to cover. That is, it goes from the introduction all the way to the end of motion: Introduction to Motion.
Unit 1.01 Introduction to Motion Schedule
The Book of Phyz - Unit 1.01 Introduction to Motion
Some Unit 1 lessons "bleed" over into Unit 2 (Newton's Laws). They serve as homework when there is otherwise no homework for students to do, such as a night following a lab day.