Just throwing my two cents in... If you guys already have a vet system in place then disregard these, but if you don't then maybe this could work for you.
Soviet Vet: Veterancy over time
Troops and units gain vet over a period of time. Ex. Vet 1 in 5 mins, Vet 2 in 10 mins and Vet 3 in 15mins. Of course you guys choose the length of time before the veterancy kicks in. Also, this vetrancy only begins only if the unit/squad gets a kill/kills, sort of a trigger for the vet to take effect.
Ostheer Vet: Conquering Vet System
Troops gain vet from the amount of points they capture. Ex. Vet 1 upon caturing 5 points, etc. Tanks and Vehicles gain vet based on the percentage of the map that you control. Ex. Vet 1 at 50%, Vet 2 at 75%, Vet 3 at 85%. Though their doesn't disappear when you lose control of the map, new units only gain vet based on the current map control.