I've made good use of a unit of 6 IC WW knights, with full command and the War Banner. They are relatively cheap and make a good hammer unit when provided with adequate support. Against a ranked infantry unit to the fore, they start at -3 CR; with seven S6 and six S3 attacks they
should be able to pull off a draw or at least not lose by much. They might even win by a point or two. Because they are WW, they will continue to be combat effective with S5 in subsequent rounds so they can tie up low-strength infantry for quite some time - enough time, for example, for the Pistoliers to show up and take the flank. Enemy units with S5 or higher are a problem though and require another plan
Still, this unit is about as expensive as two 'nilla units and the improved flexibility of two rather than one is a GOOD thing.