Hey there, Hybridwarhawk (I still think that's an awesome name).
If you're asking about completely removing an SSD in favor of a GTX 570, I would highly recommend that he goes with an SSD + 6870. If you're talking about downgrading the SSD and still getting a GTX 570, that could certainly work.
For things like Lightroom and photography, it'll be nice to have that SSD. Photoshop can be quite slow on spindle drives (especially with the way it handles scratch disk space). The performance gain from an SSD will be more than that of a slightly better GPU. The hard drive is always the bottleneck in gaming PCs
Let me know if I didn't adequately answer your question, I'm always happy to help