Oh missed all this.
I'm in the one weapon per unit camp. In Warlords they were described as having 1 heavy weapon per 5 man squad.
Quote:
"They are formed from standard combat squads armed with lasguns and sidearms, with one squat in every five man squad carrying a heavy weapon such as a missile launcher or a heavy bolter".
If you feel Moscovian that one missile launcher/unit is to much then you could make it half have HB and half ML (with ML's rounded up). That should make all "old school-ists" happy based on the above description. It's probably a bad idea though, to much confusion potential.
my two ören (swedish cent equivalent)