Well, to address the safety of the range? Based on the info Tango gave, Id say it was unsafe, but not because of the low roof. The low roof, and the wall (baffle) mentioned by FCross at another range are actually there for the safety of neighbors downrange. Tangos range sounds unsafe because there is no RSO, and the poor construction of the benches (or lack of maintenance).
Certain municipalities have a no blue sky rule wherein there should be no blue sky visible from the firing line. In some cases, ranges have to also demonstrate that the baffles installed will either keep a projectile from leaving the range, or dissipate enough energy that it is non-fatal if someone does manage to get one into the neighborhood over the berm. Both the NRA and National Association of Shooting Ranges encourage and promote this type of construction.
It sounds like the range Tango is referring to at least started out with good intentions, to avoid some liability backlash from the neighbors. But in the end, good intentions will only get you so far. Im curious to know if the range was there before the houses were built. Several years ago I looked into building a public range, and it is by no means an inexpensive venture. My naïve mind at the time thought, buy cheap land, pile dirt, no problem. There is so much more to range construction than building a backstop. I know a few people on here have their own, as do I, but when you are talking about hanging out a sign and inviting every nimrod in the free world to come shoot at your place
.. things change. I cant tell you the times Ive been to an indoor range and seen bullet holes in the bench in front of me. Its scary. Which is why some ranges are slow fire only, no mag changes, seated shooting only, and an endless list of other seemingly idiotic rules. One of the managers at American Shooting Center in Houston told me a story about one of their clay throwers malfunctioning. So they sent out someone to take a look at it, and they found a .45 slug punched through the housing. The thrower was about 250 yards from the pistol range firing line and some 45 to 60 degrees off of the firing direction. They figured that someone had been practicing mag changes, and oops! His words Dont put anything anywhere downrange that you arent prepared to get a hole in.
Diagrams of range designs are in the last half of the document.