seat61.com is great for tips and tricks on routes.
For example, from London to Basel, the quickest routes are via Paris, and the fastest routes via Brussels use a Thalys train to Cologne, which ends up being expensive. However, seat61 has a link to a tweaked a search at
www.bahn.de to add in a stop in Brussels, to ICE trains instead of the Thalys. If you book in time, these have Sparpreis tickets which are cheaper price. Flying is quicker and often cheaper, but I prefer taking the train.
I'm also going to Ljubjana in a few months for a conference. The convenient flights to Ljubjana are now really expensive. Seat61.com mentioned the route from Venice to Trieste, then with a tram and then on with another train to Ljubjana. Google Maps gets some of this route, but it doesn't pick it out, as being a nice and interesting route.