Ultimately, a straight paddle is simple. There's no messing about, you know what you're getting, and that's perfect for those of us who want to just get out there and paddle the world without looking back. Straight paddles are usually cheaper too, often the deciding factor in most purchases...
But then why the fuss over cranks?
Cranked paddles will keep your wrists straighter throughout the stroke, which means that there is less stress on the tendons. For many paddlers who use cranks, including myself, this helps to reduce inflammation in the wrists which typically leads to tendinitis.
Cranks help your paddling technique too, providing more leverage in technical strokes like draws. They also lift less than a straight shafted paddle towards the end of a stroke, so you do not lose as much momentum.
When going for a roll, I have also found it easier to feel where the paddle is in my hands allowing for a more successful first time roll attempt.
At the end of the day what feels best to you is what matters, but cranked paddles are definitely something to consider for your next investment.