It depends on where and who you intend to fight:
Open Desert (I'll use U.S. gear)
Two Armor Brigades Each has 81 tanks and 57 Bradley IFV, 20 155mm SP
One Armored Cav Brigade - 40 tanks, 124 Bradley IFV, 25 155mm SP
One Infantry Brigade, Mech - 250 Stryker IFV, 12 SP 155mm, 140...