It depends on what you're judging them on. My favourite out of those 4 rides is Spinball as I find it by far the most exciting. I wouldn't go so far as to say it was the best though, as clearly there's a lot wrong with it (build quality and throughput in particular).
RMT is the most accessible of the bunch as it's tame enough for younger riders to enjoy whilst still offering thrills thanks to the helix into the tunnel. Thirteen is a great "step up" ride, as it looks quite intimidating due to the theme but is actually great fun and not likely to put anyone off going on bigger rides when they reach 1.4m.
I wouldn't call Air a family ride purely due to the height restriction, just because your family are all able to ride doesn't make it generally true. To use examples from other parks, X:\NWO and Rattlesnake are not true family rides as they exclude a proportion of their target from riding by having overly strict height restrictions, though they are both family coasters by design