Hi Dave the welcome to IIS,
From my limited experience, everything has a trade off.
6SE is lighter, but 8SE gives you better light grasp and therefore better resolution.
Single fork arm is light and easy to use, but can't do much in terms of AP. I did however get some decent planet images using a webcam and stack the video through Regi Stax, so maybe that's a starting point?
I have since ditched my single arm fork mount in favour of a used EQ6, WAY better in my opinion.
Then there is the $$$ question. AP is a bottomless pit
so be prepared to part the wallet for decent gear, you get what you pay for.
A 8" f4 newt on a EQ6 will probably set you back the same amount in dollars, but I think it's a better set up as f4 will be much more forgiving than the native f10 of the SCT. The other alternative is the good old ED80.
Food for thought.
Bo