WAVE version 6.11 and later versions allow you to change the displayed sizes of individual signals if you wish. If the Annotation Template is not open, open it by left-clicking anywhere in the signal window, then left-click again in the signal window to return the focus there.
Select the signal of interest by pressing and clicking with the left mouse button while the pointer is near the signal of interest, which will be highlighted by WAVE when you do so. Next, press and hold and one of (to enlarge the signal), (to reduce the size of the signal), or (to reset the size of the signal to the value selected in the View panel).
You may repeat this operation with as many signals as desired. If you have not selected any signal, all signals are resized by these commands.