Formating with different aircraft types has its own issues as they each react differently due to their size/shape/aerodynamics as well as to their flying control dynamics.
Sitting behind an AAR tanker whilst sat in a Tonka when there's turbulence often meant the tanker and the basket bouncing around but the Tonka sat there, dead still with its gust alleviation doing its job.
Did a season formating on a Canberra in a Hunter and that had its own issues with different acceleration and deceleration rates. Didn't try any exotic manoeuvres that early in our careers though.