I agree w/ the 2 Gorgers sentiment. You could also consider 3 scouting/stubborn Maneaters w/ extra hand weapons. I would prefer the gorgers in your 3k game b/c the full table will limit your scouting.
These two units, while lacking the punch of an IB, will put a strategic tool in your pocket. You will have a unit or two that can disrupt your opponent's battle line by presenting a threat from somewhere other than the front. The significant advantage here is that he will have to detour a portion of his army to deal w/ your threat—presto, you've gained some tempo.
In addition, you'll gain some flexibility w/ the gorgers as you will have the opportunity to place them near a troubled spot on the table that develops after the battle begins.
I find that the choices which make your opponent change his plans or increase your flexibility pay off, but it's difficult to put a point value on them.