Impetuous.
Turn the "Pursue on Winning" rule into a Battle Card so that other elements might have it?
Usually this goes for free to Knights, Warbands, Warriors, elephants etc.
BUT, what if the less well trained Legionaries of Cannae (count as Heavy Foot) also had this for this battle?
So the Light Foot & Warband of Gauls + Spanish aren't skirmishers, so won't evade and pull the elements forward.
BUT when they recoil or even better break off 20mm, THEN the Romans have to pursue 15mm.
Not only do the Carth side break contact and the Romans have to expend pips to move back into contact (because the recoilers recoiled slightly more than 15mm),
but now the line of lights/warband is actively PULLING them in to create that concave formation that became the death nel for the Romans.
You could actually have 2 slightly different Battle Cards.
1 for pursuing on a beat. Call it "Relentless".
1 for pursuing on a break off (Pike I think would be the only different element). Call it "Impetuous".
But either way, it allows for this kind of battle specific thing occurring, without requiring a double, which would require the Spanish/Gauls to die.
Since it's a negative effect, the cost of the Battle Card could actually be negative? For Cannae specifically it doesn't matter, but perhaps for scenarios.
It also leaves the door open for a specific army/scenario in which knights etc for some reason had the discipline to NOT rashly pursue because of training, circumstances etc. so would NOT have this battle card
