That's where I was coming from too. It just seems more straightforward (and more realistic) to pick, say, 2 platoons of 3 infantry squads in WZ-551s and platoon of 6 Type 99s rather than 3 platoons each with 2 MBTs and 2 squads/apcs. The only real difference is in large games where a force like the one above would be used. With the mixed tank/infantry force you'd have 3 slots for artillery and air support or whatever, the 3 'pure' platoons would give you 9 as you don't eat up 2 each for the tanks.