USB-C is already a de-facto standard, supports a wide range of voltages and with enough current to be able to charge even beefy laptops. You also don't have to support all the complexity; if you just want to power a simple device that needs 5V with at most 1A or so, then you only need two resistors on that device.

Sure, it has some issues in some of the more complex cases (mostly because not all USB cables have all the wires they should), but I don't see any alternative that will give an overall better experience.