Thank you Lee for explaining it so plainly and for your advice
I must agree that no matter in what direction I look, I always end up with a conclusion that an upgrade would make a solid dent in my savings and any improvements won't be radical. Perhaps in a few years, IF we move to a darker location and I would like to try RGB imaging, then I could possibly look for something better.
Let's hope that this dark storm lurking in the west will go past Brisbane quickly and we will get a few hours of clear skies tonight...