Interesting... I take it there's not seperate control over character height and width? I noticed that basic HTML tags are being used for format, so does SE understand the Style attribute of HTML elements? In other words, would it understand something like <p style=''font-width: 95%;">?
I gained extra space for my description area by setting character width to 95% in PS. I kept the overall font point size the same. (I'm using the traditional Caxtion where point 6.7 is equal to the 7 in your font version). But if there is a scripted way to make the graphic template change based on text body line count or length or size, then that may offer me what I'm after...
A way to make it shift more times for more intermediate template sizes, similar to the more flexible floating midbar I use in my PS Talisman card templates.