I have enjoyed the well-priced, excellent service of the Amtrak Downeaster between Boston and Maine as well as Boston to UNH-Durham business trips. Unlike the sometimes surly Amtrak staff on the Northeast Corridor (including First Class Acela crews at times!), I have found Amtrak staff on other corridor routes such as Shore Line East and Downeaster to be very friendly, just like you imagined train conductors and staff to be.
Downeaster vs. driving
I am guessing that round-trip service from Boston, MA to Rockland, ME would be about $65, and take about 3 hours 45 minutes one-way. The driving time would be the same as the train, maybe more with a car due to breaks/traffic.
Rockland, ME is in Lyft’s Maine service area. I would guess that on summer weekends, there would be a couple Lyft drivers active, particularly if Amtrak came to town.
NNERPA’s proposed Rockland, ME service is once-a-day round-trip on summer weekends.