Thanks Dunk.
I do need to find a good planetary work flow. Been reading a lot but I'm not certain how applicable some of it might be. Experiment and see what works as you say.
I will give a lower exposure a try, I do try to underexpose a bit but not as drastic as you said so I will give it a go, it's about the only thing left to try now to get a higher frame rate anyway.
Just need the sky to play ball now.