For rendering, GTX 760 4GB sounds a good deal, but I'd probably look on a model that exhaust heat outside the case (more closed heat sink). For me it looks like this card may exhaust most heat inside the case. As all parts of system must stay cool, there is a risk that heat inside the case jumps too high. Maybe PSU will then get too warm air and it's fan will spin up... in a worst case PSU's performance will drop and you get odd system issues.
that glowing onyx material is really cool. maybe needs some rounded edges all around to give it a little more detail, since its such a simple striking design.