Allow manually defining scale steps instead of using ratios

I'd much prefer to be able to define the individual steps/sizes of the scale manually instead of having it generated based on a modular scale, which is something I simply don't believe in. (A part of my soul dies every time a designer talks about the golden ratio and visual harmony) – but more importantly, I've had negative experiences with rounding issues that were caused by using sizes that aren't rounded to whole pixels.