Ancalagon
Dusty Dragon
Does balance between PCs matter? Absolutely - in fact I think it's the balance that matters the most. The disparity between a naively designed character in 3.x or pathfinder and an optimized one is immense. It's much better in 5e.
Balanced encounters - bah. Those tools are only there so that the GM knows what she is doing. A group of 1rst level characters may have to deal with a half dozen marauding ogres. That's "too powerful" for first level characters you say? Well if they want to go fight them "mano a ogro" sure - and they deserved to be clubbed and have their bones eaten. But there are plenty of ways low level PCs could deal with such a threat. They just have to be smart about it.
Balanced encounters - bah. Those tools are only there so that the GM knows what she is doing. A group of 1rst level characters may have to deal with a half dozen marauding ogres. That's "too powerful" for first level characters you say? Well if they want to go fight them "mano a ogro" sure - and they deserved to be clubbed and have their bones eaten. But there are plenty of ways low level PCs could deal with such a threat. They just have to be smart about it.