My grandson and I recently went from Rome to Munich. We took Italo (which I generally prefer over Trenitalia) from Roma Tiburtina (which I much prefer over Termini), leaving 08:55 and arriving at Bologna Centrale at 11:00. We connected to the EC84, operated by the Austrian OEBB company, leaving Bologna at 11:52. It stopped at Innsbruck Hbf at 16:36.
As mentioned above, the scenery is pleasant between Rome and Florence (what you can see of it at 250 km/hr), but from Florence to Bologna is mostly in tunnel. Soon after leaving Verona you enter the Adige Valley, with interesting views of sheer granite cliffs, endless vineyards and the occasional medieval castle. My preference is the left side of the train for the northbound trip. Look for a spectacular view of the Europa Bridge and the Sill River valley a few miles before arriving in Innsbruck.