I bought the first game quite recently and that is a superb game, with some minor issues, for me personally, due to playing Transport Fever 2, which uses slightly different signalling methods, but it became a minor point after playing it for a while.
Anyway, Railway Empire 2 has similar difficulties initially, because a few things have changed from the first game, but once you get used to those differences, it all becomes clear.
As with the first game, the sound and graphics are gorgeous, especially on the ride-along. Track construction is much simpler and the game feels very polished overall.
There is one issue, but again this is personal to me, you can change the size of the UI, which I HAVE to do, but this does obscure things, pretty badly at times and there is no way to move windows out of the way, so it becaomes a case of camera adjustment, which isn't ideal. I have adapted to that, but it would be easier if you could just move windows out of the way instead.
I have the DLC also and that gives you huge oportunities for creating your rail empire in different parts of the world, no-doubt with their own individual challenges, along with some amazing scenery.
All together, despite my individual issue, this is a fantastic game if you are a fan of this genre :-)