its a good gunline, My only questions would be about having 2 cannon, perhaps swap one for mortar, maybe. I would probably use fewer flagellants and boost my Greatsword unit to 20 instead. The wizard I would advise to ditch dispel scroll, purely on fact that you have 5 dispel dice, I would reinvest points from dispel and staff into Rod of Power, so you can either save dispel dice or power dice depending on if you are magic dominant or not, more flexible in a tourny list!
What are rough tactics, because the way i would use it, the knights + pistoliers go flanking and threaten the enemy rear (slowing their advance), whilst artillery find a nice cosy hill with greatswords + flaggies in front and handgunner on each flank,