New scope recommendation for astrophotography?

[Quetzalcoatl72]

I'm looking for an OTA to go with my neq6 purely for astrophotography, I currently have a celestron nexstar se c5 which needs to be replaced and a ED80 which I haven't used that much so I need to keep that. I've used my c5 for both planets, nebula and galaxies all came out great imo, but I'm after a scope that can do all of that but bigger and brighter! I've looked into the C9.25 but I heard it's only good for planets, surely that's just them being picky, something about poor wide field of view? Isn't that just if you want to image larger nebula or galaxies? then surely you can reduce the focal length with a piece of kit? My budget is about £1700, again I'm after larger images in planets such as mars, mercury, neptune etc, and nebula like the eskimo, ring and dumbell, and other smaller objects of interest.

I'm using a canon 600da, and a asi120 as a guidescope, currently debating whether or not to get a proper CCD because my dslr doesn't seem to pick up certain nebula for some reason, i've never imaged horsehead. Not sure if that's light pollution or what, which is bad in my area might I add, but I've gotten great pics regardless, I have a filter for that which I haven't used yet, and the other piece of kit I have is a x2 barlow 2". With my budget can I get something that can do all of the above? or do I need 2 scopes like what I've been hearing a lot, which I don't understand because my little c5 can do all. Thanks. I'll attach pictures of what my c5 can do: