Regional Train 1st class?

I found the 1st class is usually empty on regional trains. Regular everyday locals that take regional trains to work don't sit in 1st class. I took regional train from Augsburg to Fussen to see Neuschwastein castle recently and bought 1st class ticket thinking 2nd would be over run with tourist and was the only one in the 1st class car for one hour ride. It depends on the time of year and Wurzburg is not a major tourist destination.

Morning Regio trains (RE60 and BR68) from Darmstadt to Frankfurt are well filled up during the week (rush hour). No seat reservation. First class improve chance to get seats.

Pictures of train used for RB68: https://www.rmv.de/c/de/fahrplan/linien-netze/fahrzeugtypen/regionalzuege/twindexx-vario-doppelstock-elektrotriebzuege/twindexx-vario-doppelstock-elektrotriebzug-main-neckar-ried

RE30: https://www.rmv.de/c/de/fahrplan/linien-netze/fahrzeugtypen/regionalzuege/doppelstockwagen-lokbespannt/doppelstockwagen-lokbespannt

Hint: Regio trains can be used with Deutschland-Ticket as hop-on-hop-off.

Leaning toward taking an ICE on the 2nd leg. The regional train originates at Frankfurt Hbf, so it could have enough people to make all of you sitting together iffy. You could reserve 4 seats around a table on the ICE, and it is nonstop from Aschaffenburg, so you will get to Wuerzburg 1/2 hour sooner than with the regional train.

You have two ways that are viable to get from Darmstadt to Wurzburg by train. if you use the DB website it will send you to Aschafenburg and then to Wurzburg. If you use this route you can take either the regional or the ICE from Aschafenburg. Since those trains originate at that location you should be able to get a 4 person seating arrangement.

But you also have the faster option of taking a regional train 15 minutes north to Frankfurt and catching an ICE from there straight to Wurzburg. this is the fastest connection. And with the ICE you can select your seats ahead of time. I would do this, as the Frankfurt bahnhof is extremely easy to get around, has excellent services available, and is all on one level, so there's no stairs to haul your luggage up.

I have a 1st class ticket for regional trains in Hessen and often sit alone depending on the route. If the train is full, people are allowed to come in and sit there, but that doesn't happen that often. I like it cause there are plugs there for my phone and the seats have a bit more room.