Best route from Luxembourg to Frankfurt (Aug 24)?

Hi everyone!

I’m looking for advice on the best route to travel from Luxembourg to Frankfurt on August 24th using a 1st Class Interrail Pass, aiming to avoid mandatory seat reservations (or keep extra costs to 0€).

So far, the best option I've found is this one:

• 09:21 Luxembourg ➔ Trier (10:21) | Replacement Bus

• 10:41 Trier ➔ Koblenz (12:36) | RegionalBahn (RB)

• 12:56 Koblenz ➔ Frankfurt Main Hbf (14:21) | ICE

As far as I know, this route requires 0 € in seat reservations (since ICE trains within Germany don't require mandatory reservations, and RB/buses don't either).

A couple of questions for those familiar with the area:

1. Is this indeed the best connection, or is there a faster, more scenic, or more reliable alternative?

2. Are 20-minute connection times in Trier and Koblenz safe enough considering potential replacement bus delays or DB connections?

Thanks a lot for any tips or recommendations!