I have some tips for tightening up the formation.
Lead should always be at less then full power so the Wingman has thrust in reserve to hold position.
When the Wingman falls behind Lead should turn enough so the Wingman can use lead pursuit to close the distance.
This works better than Lead cutting throttle while flying straight.
The biggest gaps tend to open when Lead and Wingman fail to change AOA together. Changing angle of attack changes your speed.
When you fly a loop this becomes obvious, the key is pulling up at the same time and same rate of pitch change.
It's easy to get sucked out of position into a tail chase. Wingman has to focus completely on staying in position while Lead is focused on smooth repeatable maneuvers so the Wingman knows what to expect and can anticipate where he has to add power.
Get in position on the runway, try a 45 degree offset to start, and maintain it through the flight instead of joining up later.
Plan your routine so Wingman is on the inside of turns.
AH smoke trails are so short and thick you may look better without it.
With practice you will be able to stay within about 30 yards. Lag will not let both of you see the same distance so go by the Wingman since the Wingman is holding position on his PC and should look pretty stable on his film.