Rob, when you refer to GW warband games, do you mean the truly vintage stuff like Realms of Chaos, where you generally have one or two heroes, three or four very small squads and a few big nasties (most of them generated by rolling on numerous d1000 tables!) or do you mean the more recent stuff like Mordhiem, where it is literally a dozen individual guys with more or less the same profiles but some variation in skills and kit?
I ask because if its the later you might need to bend the army selection procedd, or make up some of your own system to cover that sort of game. The core mechanics certainly support it (as seen in the Table Fables) but you'd have to use the power of Mental Thinking (tm) to put that together. I think Ernie said he's very much up for accepting player submitted content, so much like Mordhiem was a 'mod' for Warhammer there's almost certainly mileage in doing the same thing here and publishing it as a downloadable web article some time in the future.
Does that make sense?