Thank you for all the tips. I only used trainline to help look for options. However, sometimes, the connections they suggested sounded way too tight, thus my original question. I also found that they had bad information, at times. A couple of trips they had as nonstop had one stop. And they also listed a train route totally within Italy run by an Austrian company that cannot be accessed. but the website gave me an outline.
Once I saw which trains were running at what time (regional, express, company), I went to the specific train company to map out my options and make my purchases.
I was surprised and disappointed to see that the regional trains for our trips were actually more expensive, as well as slower, than the fast trains, at least when comparing the cheapest, non-refundable fares. I had been reading online that they were much cheaper but that is apparently only for cancellable/refundable tickets. Fair enough, but a surprise.
For our trip from Milan Centrale to Bolzano via Verona, we did purchase a non-refundable ticket for the Verona-to-Bolzano leg. We're taking a regional train from Milan to Verona early enough that we can take another regional train and still make our reservation if the first gets cancelled. If we have to take the second train, our layover is still over an hour before departure of the fast train to account for a delay.
If everything goes smoothly with the first regional-train departure, since the old part of Verona is within walking distance, we'll enjoy checking the town out for a couple hours before taking our fast train to Bolzano.