Mostly talking about Tuscany, Piedmont and Venice. I get it that for new duchies or republics some new creations are in order, but for already established states (or states that had existed not too long before the start of the timeline, like Venice) I would have preferred the flag before 1848 (with the tricolour being the common confederal flag). I am just a fan of the old Venetian and Tuscan flags.
Sorry, guys, but, as I said before, the flags were chosen IOTL and should be even more obvious ITTL (when they are chosen before there is a proposal for the Italian Confederation). I fear you underestimate the patriotic feeling of 1848, and the appeal of the Tricolore.