It's an unfortunate fact that many GPUs run very hot. 75c is about average for a stock GPU under maximum load. At this temperature the GPU should have a 2-3 year lifespan.
Serious overclockers and those who want their GPUs to run optimally for many years always look into improving cooling. That might be as simple as purchasing an extra case fan and aiming at the GPU or as complex as buying a custom cooling unit for the GPU and removing the stock cooling unit that was included with the Graphics Card, or looking into liquid cooling custom coolers. These units can add as much as $150 USD to the cost of the GPU but are usually worth it in the sense that the GPU can be overclocked and will not surpass around 60C which is a very safe, stable temperature for any hardware component.
It's commendable that you're concerned about your GPU's running temperature and, if you can spare the money, aren't afraid of a few screws and playing around with thermal paste, might want to consider a custom cooling unit. Just be very aware of the risks of static discharge damaging components when you work on them and read a few guides on what you're doing before taking the plunge and buying a custom cooling unit.
A less technical, cheaper solution would, as stated above, be purchasing an extra case fan and aiming it directly at the GPU.