That's my way of travelling too, at least when I travel alone.
Still, I think you'll be running out of time in some of those places, especially Venice, Parma, Aquileia/Grado/Trieste, Ravenna and Bologna.
Looks like you've taken care of your Mondays, always tricky.
If Velleia proves too difficult (don't know, never been there), consider Marzabotto instead. Just a short train ride south of Bologna.
If you take a day to see Monselice and Este, you might as well visit nearby Montagnana.