maybe because of HD Resolution from Screen?
I have the same small width of streets, and if I set any zoom, it Shows them smaller for factor10 - 20méter is 200 meter and 2km it Show me 20kilometers.
edit
have paste this in the sys txt,
[map]
3d_max_tiltlevel=1000
3d_max_zoomlevel=1500
3d_min_zoomlevel=30
3d_max_zfar=30
and now it Show me the map and street in a size how I like it, but no zoom - it is o.k for me, maybe it help someone too
what from this 4 commands is the one that make all bigger, don´t know - but one of them work:-)