Currently SimBrief and Navigraph Charts do not use the same routing method, so it’s normal for them to give different results. SimBrief uses routes from a database, whereas Navigraph Charts generates routes ,mostly from scratch.
There are plans to incorporate the Navigraph Charts generator into SimBrief at some point in the future.
You should know that in the examples you posted, just because a route uses DCTs, does not mean it is somehow invalid or faulty. In fact, in your ENBR to EDDF example, the SimBrief route is “correct” according to Eurocontrol, while the Navigraph route is not.
Neither of the LICA to LIMC routes are correct according to Eurocontrol, but I’ve added a better route to SimBrief’s database now.
For LEPA to EGAA, SimBrief’s route was not very good. I’ve removed it from the database and added a better one from Eurocontrol.