Hello and welcome to Ice in Space!
As an owner of a Nexstar series scope, I'd suggest looking elsewhere...not because they are necessarily bad scopes (I love mine!), but because they are overpriced here in Australia (I brought mine with me when I moved here) and there are much better deals to be had.
I'd recommend something like a Skywatcher Dobsonian with Synscan/Goto. Be aware that you do pay a lot extra for the computerised systems over the non-computerised scopes, but IMO having the tracking capability is worth the extra, as it keeps the object in view while you're observing. Otherwise you need to nudge the scope to keep it in view. Not a big deal either, but it depends on what you're after.
This busts your budget a bit though...even the 8" with goto is $1399 new, so it might be worth keeping your eye out in the classifieds.
Bigger is better too, but IMO an 8" is a bit of sweet spot between what you see and how big and heavy it gets. A 10" would be mighty temping for the extra $300 and you might find that'd be sufficient for visual...it's a tough call.
For photography...like Glen says, it gets expensive fast once you get into that
maybe start off by taking a few night sky exposures with the equipment you've got, you'd be surprised what you can see with 10-20 second exposures from a dark place
Later on you could move onto eyepiece projection, and a tracking Dobsonian would be good for similar length exposures, but that'd be about your limit because of field rotation. For longer exposures, you need to use an equatorially tracking platform, such as an astrotrac or polarie, or a decent equatorial mount...
Unfortunately, there is not one scope that suits every purpose so we're destined to "make do" or have multiple scopes