I've had a thought bumbling around in my head for a while about tank/air crews. I might have outlined it before, but the best infantry killing tank is still the lighting with HE or HEAT right?
If you were running a squad based on alternate Lib/Tank pulls then teams of three would be the simplest - gives you Lib a reargunner and the third man can drive a Lighting anti-infantry "outrider" for the Mag.
The Outrider's job is to kill threats to their MBT chum - not run away or get involved in other things - Lightings tend to be smaller, faster and less valuable targets for infantry AV. I would imagine them flanking and blasting away at AV positions while those AV guys are concentrating on the MBTS and don't see it coming. You still have to pick your fights and stay mobile and alert.
To a lesser extent the Mags can support each other - each one covering the flanks of another one - but I think a Lighting would be faster and a better use of people and points.
Sadly at the moment against Infantry who are remotely equipped to fight them mags are more raiders than ... well ... Tanks.