[Crash Nebula]

Hi everybody, haven't posted here in a long time - a few might remember me. I have had my scope for 10ish years (8" Saxon dob) and have managed to never upgrade lenses due to wavering interest in the hobby during my teen years and being too busy with university up until now. I am primarily interested in planetary and deep space viewing. Is buying a kit the way to go, or are the Celestron ones pretty average? I have found a few through eBay that seem to go for pretty cheap, including a Meade one - from what I remember, Meade is pretty good? What should I look for in a barlow? I'm pretty clueless, so any help is appreciated. I probably only want to spend a couple hundred dollars.

I'm also interested in astrophotography, too. I've been using my smartphone to get some basic shots of the moon/saturn, but I am pretty clueless when it comes to doing shots of nebulas and galaxies. I have a Canon DSLR, is it easier to get a mount and use that, or buy one of the CMOS webcam things I've been seeing? Would rather not spend ~$600 on a Celestron one, but all the other ones available are around $20 and seem pretty garbage. Doesn't seem to be any in-between... any advice?

Thanks!!