I find it can be very difficult to judge the position of a tiny pin-point flash of light, and quite often I start off thinking I've seen something odd, only to find that, with careful attention, the flashes (even if they are irregular in frequency) appear to be in a straight line, so I'm happy to conclude they are very high altitude planes or tumbling satellites. The wider flashes could perhaps be sparking electric trains? We have rail services round our way that are powered by a third rail, and at the joins there are often very bright flashes. Close up, they can be spectacular and loud, but from a distance we just see a part of the sky light up. I've see a few other oddities - and I think I've posted about at least one of them here, a bright "extra star" that appeared for a while, making what would normally be a familiar constellation suddenly look unfamiliar.