I personally don't mind the dark and broody image, it also has a very 3D feel to it. It has turned out quite well for a limited amount of exposure overall.
I've also been shooting at Gain 139 with a F/5 refractor. I haven't done a lot of LRGB imaging with it but I have found that 300-400s in Ha with a 3nm filter is optimal. 60s LRGB for your location sounds quite reasonable though, doesn't sound like the darkest of skies
