My sight regrettably is dimming with age.  My eyes are well assisted but it still doesn't prevent small detail being hard to read.

How would I go about resizing the panel, to about twice its present vertical dimension?

You could try editing the panel.cfg file, double the window size numbers.

But unless you know what you're doing I don't recommend it, unless you decide to read the Panels SDK.

 

Save a backup of panel.cfg before you edit things, if it gets messed up you can go back to square one.