Assuming I am also reading the proper matrix in the commercial ACS, I agree that it appears the only maneuver to be accomplished in that section is Steep Turns.

You only need a minimum of 25 hours of multi time (if planning on going to the regionals) so renting any time beyond that is likely just wasting money unless you have access to an inexpensive multi.

So how to get the other 75 hours? You could just burn holes in the sky using your PPL in a single. Maybe go get checked out at your local flight school in their single engine to build some currency. Then after you feel comfortable, begin a multi course toward a Checkride. Plenty of people get their commercial multi without getting their commercial single.