In the 1750 -60s Plans of Discipline such as Bland's or Norfolk the normal size of a company was to be approximately 40 men in the line units, excluding the Musik and Hatchet men. Typically this could be as low as thirty men fit for service per company and on campaign this might be even less.
The companies were sized with the tallest men in the front rank. Each rank was also sized with the tallest men on the other ends of the line and the shortest in the center. ( I suppose this is moot with toy soldiers!)
In a company drawn up for exercise in one rank, with three officers present they would be equally spaced along the front a few paces in front of the ORs.
If you were viewing the company in front of you, the Captain would be in the center with Lieutenants on either side.
The NCOs would be at the left end of the line.
The Musik would be to the left of the NCOs, and if there were Hatchet men or Pioneers, they would be to the left of the Musik.
When the ORs were formed into three ranks the Captain would be posted to the center front, with the two junior officers posted at the right and left ends of the center rank.
The NCOs are posted to the left with the Musik to the left of them. These command sections are posted on the first and third ranks, with the Hatchet men to the left of the first rank.
During movement on the field it was the norm for the NCOs to move as needed to keep control of the men, and it was not unusual to have one posted at both the right and left.
It was also typical to have the Musik posted to the center front just behind the officer and a few paces to the front of the men. This was to insure that the commands could be communicated by drum.
To the front of this command group of officer and Musik would be the Pioneers in an advanced position.
There are many minor variations, and the Drill of 1764 continued to make adjustments to these arrangements, and additional changes were always adopted on active campaign.
Hope this helps a bit.
Ken
