Determining device families without using separate resource folders

Hello,

I would like to change the font for one specific device family in my project ("round-240x240", launcher_icon height="33" width="40"), as it is too big.  As that's the only thing that is different, I don't want to use separate specific folders, and instead wish to define the fonts in the onLayout() function.  I already know how to define a specific device, but when it comes to a whole family is there a more efficient way? And also, how do I determine the specific resolution? 

This is what I've got so far:-

    function onLayout(dc) {
        setLayout(Rez.Layouts.WatchFace(dc));
        if (/*something like family == "round-240x240" and resolution(??)*/) {
            smallFont = Graphics.FONT_SYSTEM_XTINY;
		} else if (screenWidth == 208) {
			smallFont = Graphics.FONT_SYSTEM_TINY;
		} else if (screenShape != System.SCREEN_SHAPE_ROUND) {
	        smallFont = Graphics.FONT_SYSTEM_SMALL;
        } else {
	        smallFont = Graphics.FONT_SYSTEM_TINY;
        } 
        
    }

Any advice appreciated, thanks in advance.