As rails are very visible on the overhead map I chose rail pieces to create the letters and to my surprise they turned out way better than I expected. This is mainly because the rails have 45° rotations which can be put to very good use when designing the letters.
So I went on and gave all my (still few) POIs a small label
Not that there's already one because of the train stop, mind you, bit I just think it looks cool, so there ya go 
On greater zoom level the train stops vanish but the text labels can still be read:
