[Urendi Maleldil]

I don't know how to express this mathematically, but maybe a Weapon Index (WI) number of 1 could equal a weapon with these characteristics:

10kT space
10kT structure
10 Normal damage at range 1
1 max range
.1 decay
10% to-hit bonus
1 reload rate
10 supply usage
10 each cost min, rad, and org

Using this hypothetical weapon as a base and some mathematical formula to boil it down to one number, you could then use it to rate the effectiveness of all other direct fire weapons.