For refueling I've recently been using the cybersyn mod, which let's you easily create a refueling stations that your trains will automatically go to when they're low on fuel (with exactly how "low" they need to be being configurable in the mod settings).
I just plop down a refueling station, and a requester station next to it that refuels the refueler and I'm done. Don't have to worry about it again.