After lotta hours playing BECTI i almost achieved to have a half good ai commander behaviour (on the enemy side of course)
1. Map, its important to avoid mountains bettween the two bases, ai seems to do not recognize roads, most with tanks, i like Malden 2035 for example.
2. AI size teams, i suggest around 20 units, that way at least half of them will reach the fight (set all slots and bettween 6 and 8 enemy teams).
Set 20 units for your side and get rid of ai units, most time they cant even reach a town.
3. Most important setting IMO is to set Divided Towns, money will flow to the Ai and probably they will make a decent fight.
4. I added better AA squads to make their base more hard to hit by planes.
All this just trying to revive OFP cti missions xD.