Two seniors want to spend April in Italy

On mainland Italy, just east of Capri, Sorrento was a great base for trips to Pompeii, Herculaneum, Naples, the Amalfi Coast, and, yes, Capri.

If it were me, i would have Florence be my home base if you weren't wanting to move around. Somewhat centrally located, large train station, and airport with flights daily to USA.

(personally for a full month, i would split between 3 places at 10 days each, but thats me)

Verona is a nice hub with train service in all four cardinal directions. Lots of nice towns reachable in one hour or less, but Florence or Bolzano tend to take 1.5 and Torino would be 2 hours each way.

Florence, Bologna, Alba, Siena, Spello,
Verona, Vicenza to name a few.

Fererra or Padua with similar quick access as Bologna to day trips. I like Florence as well but think the Bologna area to be a good hub.

Sorrento, Florence, Verona.

The suggestions provided by others sound good to me, but I am firmly in the split-the-time camp. I would find a full month in one location too limiting. I take a lot of day-trips, but repeatedly spending 3+ hours on trains or buses on the same rail line or highway would drive me nuts.

However, I realize you may be planning to rent a car, in which case your universe of nearby options will be much larger, as long as you're interested in exploring a lot of small towns.

@acraven, I am with you, but was trying to comply to moderator's recent request for 'sticking to the topic' ;-) I guess it all depends on how many day trips one takes, but I also think day trips are false economy - both for time and $ (travel costs) - but it works for many, so I try to keep my preferences on the down low.
My suggestion of Ferrara would make a nice 2 week stay of planning to be active, and the ability to head in numerous directions. But given the Italy chill this April, I wonder if a second location in Southern Italy would be a nice option?
In this day and age with so many apartment rental options, there can be adequate savings in a one or two week rental to make it worth a move. Not all provide monthly savings for short lets.

I, too, would split it up into 3-4 places, given that you have a month.
Bologna - Ferrara, Padua, Ravenna
Florence - Siena, Volterra, San G, Montepulciano and all small hill towns, etc.
Orvieto - Perugia, Assisi, Spello
Sicily - spend the entire month