Hey there,

I don't think there are rental cars available at Lichtenfels, because it is actually a rather small station.

However, if you want to check out Leipzig, why not pick up a car there? It should take about 2-3 hours to drive to Coburg from there and if you have a little more time, I can highly recommend going to Weimar and Erfurt too.

And sorry, but I can't really help you with advice for sights and a translator in that area, but hopefully someone else on FT will be able to help you.