The suggestions are usually placed higher because of low quality power supplies. Corsair is a quality unit, which can deliver stable wattage even if it comes to its maximum output. It has 80 plus certification too. However, if you want, you can take CX 500 power supply instead of CX 430 - it shouldn't be much more expensive.
Sure, it's always worth going for higher end graphics card - the question is if it fits your budget.