I am testing a radical idea. Extra light infantry carriers totally unarmored.
You can have a 7 ton hovertruck, carrying one foot platoon at a speed of 9/14 (12/18 if you use fractional accounting) for about 17BVs and costing some 60k cbills. A wheeled 5ton truck, build with fractional accounting, also reach 9/14 for 7k cbills and less than 10BVs - it is just 6x6 military truck as used today by armies around the world.
You cannot use them in a open map but in urban warfare or another map with enough hills and forests, you can sneak around at high speed and deploy infantry quickly.
In combination with other combat units, you surround and block enemy units. Unless the enemy units carry dedicated anti-infantry weapons conventional infantry is quite hard to eliminate even in open terrain.
Remember that even if the carrier is destroyed there is a 4 in 6 chance that the infantry inside survives - does not matter if you have armor or not (this is metagaming thinking, I know).
Sounds suicidal but the actual changes that the infantry is hit before disembark is small, and after that the infantry carrier cannot help much. In a city map, with 12 cruise speed it takes you just two turns do disembark your troops on the other edge.
The reasoning behind is that the canon APC carrier is much slower and takes much longer to get to the target hex and deploy the infantry. Even a Heavy APC (wheeled) is not so well protected and move at only 6/9 making it an easy target.