Inch decimal wont change font size for new dims created

I have inch decimal and txt height 0.125 giving too small a text on new dimensions.

I see I used inch decimal for previous dims which measuring their height they are 1.26inch tall, if I alter the properties for inch decimal to 1.26 in an efort to get new dims their size, then they update and go too big,

With inch decimal chosen in dimensions, I create a new dimension and its minute, alter inch decimal to something silly like 10inches, and create another new dimension, its still minute, no change in size, but now the existing ones are massive.

Help !