I think the flames look great, going by those videos posted and seeing other engines at night in person I would have to agree more blue and red flames...but again I trust Oleg and his research on the different fuels and factors that I have no idea about.
My main concern is the flame reflections. In all the real videos posted you don't see any reflections of the flames on the aircraft. Where in the night video posted by Oleg it almost looks like a police car light reflecting off the aircraft.
Make the flames more red and blue, reduce reflections and I think we have a winner. Great update thanks!
Flying at night is going to be awesome in BoB!