When I choose a font size for use in a graphic I usually opt for font size menu dropdown defaults like 6, 8, 9, 10, 11, 12, 14, 18, 24, 30, 36, 48, 60, or 72. If I’m working on something large (like an A3 poster) I need much larger fonts. I’m always tempted to keep these as powers of 2 (e.g. 128, 256, or 512). But why? Am I just being superstitious! Does font size have any technical implications? Is choosing 512 in any sense better than 513 or am I actually free to choose whatever looks best?
In the analog days, typefaces came in specific sizes for the simple reason that manufacturing of type in metal and wood required it.
In the digital age, you can pick any sizes you want. You can set your fonts to 512.34492 points if you’d like.
The size is really a visual design issue. Use the size appropriate for the design. The actual numeric size is irrelevant.