Are we ever going to get trains / minecarts?

Yes, both are some of the highest voted suggestions, were on the list of what we'd like to do and as such we intend to introduce those after Early Access.

You can also still vote on them here:
https://eco.canny.io/feature-suggestions/p/trains - For Trains
https://eco.canny.io/feature-suggestions/p/minecarts - For Minecarts