Construction, battle in orderly manners and military infrastructure (supply and retreat) is what Roman’s at this point did best. They were usual not good when things became chaotic - but legions were at this point given a lot of autonomy - and Caesar’s troop had a lot of experience. Caesar wanted a lot of slaves/gold - I would think he best chance to win would be to slaughter as many as his south-Gaelic Allie’s and plunder the Roman’s supplies - while some troop keep Caesar occupied